Multiple targets match implicit dependency for linker flags エラーの解決法

#FirebaseでGoogleSignInを導入したらエラーが発生。

share extensionを使った時も同じようなエラーが出た。

#解決法
###podfileを修正

以下を追加

  pod 'GTMSessionFetcher'

#解決後

# Uncomment the next line to define a global platform for your project
platform :ios, '10.0'
use_frameworks!

def google_utilites
  pod 'GoogleUtilities/AppDelegateSwizzler'
  pod 'GoogleUtilities/Environment'
  pod 'GoogleUtilities/ISASwizzler'
  pod 'GoogleUtilities/Logger'
  pod 'GoogleUtilities/MethodSwizzler'
  pod 'GoogleUtilities/NSData+zlib'
  pod 'GoogleUtilities/Network'
  pod 'GoogleUtilities/Reachability'
  pod 'GoogleUtilities/UserDefaults'
  pod 'GTMSessionFetcher'
end

target 'myApp' do

  google_utilites

  pod 'Firebase/Auth'
  pod 'Firebase/Database'
  pod 'Firebase/Storage'
  pod 'Firebase/Analytics'
  pod 'GoogleSignIn'

end

target 'shareExtension' do

  google_utilites

  pod 'Firebase/Auth'
  pod 'Firebase/Database'
  pod 'Firebase/Storage'
end