Linker error in Xcode build 10.1

Trying to build my unity app (firebase) on 2018.3.8f1 in Xcode 10.1 using xcodeworkspace file and getting the following error.

/clang:-1: linker command failed with exit code 1 (use -v to see invocation)

IAP and Push Notification have been enabled for this app. Further the last time I got this error my previous developer pointed me to this resource https://github.com/googlesamples/google-signin-unity

From what i recollect at that time he asked me to replace the google signin files with the ones from the github link. I tried it this time and it did not work ( I confess I am not sure if I did it correctly?)

Here are log details in Xcode for the linker error

Code (CSharp):

1. Ld /Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Intermediates.noindex/Unity-iPhone.build/ReleaseForRunning-iphoneos/Unity-iPhone.build/Objects-normal/armv7/swatantra normal armv7 (in target: Unity-iPhone)
2.  
3.  
4.     cd /Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19
5.  
6.  
7.     export IPHONEOS_DEPLOYMENT_TARGET=9.0
8.  
9.  
10.     /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -arch armv7 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS12.1.sdk -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/Bolts -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/FBSDKCoreKit -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/FBSDKLoginKit -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/FBSDKShareKit -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/FirebaseAuth -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/FirebaseCore -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/FirebaseDatabase -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/FirebaseInstanceID -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/FirebaseStorage -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/GTMSessionFetcher -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/GoogleToolboxForMac -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/GoogleUtilities -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/leveldb-library -L/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos/nanopb -L/Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19 -L/Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19/Libraries -L/Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19/Libraries/Plugins/iOS/Firebase -L/Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19/Libraries/Plugins/iOS -F/Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Products/ReleaseForRunning-iphoneos -F/Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19/Pods/Crashlytics/iOS -F/Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19/Pods/Fabric/iOS -F/Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19/Pods/FirebaseAnalytics/Frameworks -F/Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19/Pods/GoogleAppMeasurement/Frameworks -F/Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19/Pods/GoogleSignIn/Frameworks -filelist /Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Intermediates.noindex/Unity-iPhone.build/ReleaseForRunning-iphoneos/Unity-iPhone.build/Objects-normal/armv7/swatantra.LinkFileList -Xlinker -map -Xlinker /Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Intermediates.noindex/Unity-iPhone.build/ReleaseForRunning-iphoneos/Unity-iPhone.build/swatantra-LinkMap-normal-armv7.txt -miphoneos-version-min=9.0 -dead_strip -Xlinker -object_path_lto -Xlinker /Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Intermediates.noindex/Unity-iPhone.build/ReleaseForRunning-iphoneos/Unity-iPhone.build/Objects-normal/armv7/swatantra_lto.o -fembed-bitcode-marker -stdlib=libc++ -fobjc-arc -fobjc-link-runtime -ObjC -lBolts -lFBSDKCoreKit -lFBSDKLoginKit -lFBSDKShareKit -lFirebaseAuth -lFirebaseCore -lFirebaseDatabase -lFirebaseInstanceID -lFirebaseStorage -lGTMSessionFetcher -lGoogleToolboxForMac -lGoogleUtilities -lc++ -licucore -lleveldb-library -lnanopb -lsqlite3 -lz -framework CFNetwork -framework CoreGraphics -framework CoreText -framework Crashlytics -framework FIRAnalyticsConnector -framework Fabric -framework FirebaseAnalytics -framework FirebaseCoreDiagnostics -framework Foundation -framework GoogleAppMeasurement -framework GoogleSignIn -framework LocalAuthentication -framework MobileCoreServices -framework SafariServices -framework Security -framework StoreKit -framework SystemConfiguration -framework UIKit -weak_framework Accounts -weak_framework AudioToolbox -weak_framework CoreGraphics -weak_framework CoreLocation -weak_framework Foundation -weak_framework QuartzCore -weak_framework Security -weak_framework Social -weak_framework UIKit -weak_framework CoreMotion -weak-lSystem -force_load /Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19/Libraries/Plugins/iOS/NativeKeyboard.a -all_load -framework Security -framework MediaToolbox -liPhone-lib -framework CoreText -framework AudioToolbox -weak_framework AVFoundation -framework AVKit -framework CFNetwork -framework CoreGraphics -framework CoreMedia -weak_framework CoreMotion -framework CoreVideo -framework Foundation -framework OpenAL -framework OpenGLES -framework QuartzCore -framework SystemConfiguration -framework UIKit -liconv.2 -lil2cpp -lFirebaseCppAuth -lFirebaseCppCrashlytics -lFirebaseCppAnalytics -lCrashlyticsiOSWrapper -lFirebaseCppDatabase -lFirebaseCppApp -lFirebaseCppStorage /Users/xxxxxyz/iOS\ builds/new\ ui\ 8-15-19/Libraries/Plugins/iOS/NativeKeyboard.a -framework StoreKit -framework CoreLocation -weak_framework Metal -lPods-Unity-iPhone -Xlinker -dependency_info -Xlinker /Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Intermediates.noindex/Unity-iPhone.build/ReleaseForRunning-iphoneos/Unity-iPhone.build/Objects-normal/armv7/swatantra_dependency_info.dat -o /Users/xxxxxyz/Library/Developer/Xcode/DerivedData/Unity-iPhone-halsmpjssjgsghdhpgbyibxicnoi/Build/Intermediates.noindex/Unity-iPhone.build/ReleaseForRunning-iphoneos/Unity-iPhone.build/Objects-normal/armv7/swatantra
11.  
12.  
13.  
14.  
15. Undefined symbols for architecture armv7:
16.  
17.  
18.   "_OBJC_CLASS_$_FIRDynamicLinks", referenced from:
19.  
20.  
21.      objc-class-ref in libFirebaseCppApp.a(invites_receiver_internal_ios_fe43142c9b5429d3e0c956b7297ce932.o)
22.  
23.  
24. ld: symbol(s) not found for architecture armv7
25.  
26.  
27. clang: error: linker command failed with exit code 1 (use -v to see invocation)