Update AppAuth and GTMAppAuth dependencies. (#517)

GoogleSignIn.podspec

@@ -34,8 +34,8 @@ The Google Sign-In SDK allows users to sign in with their Google account from th
   s.ios.framework = 'UIKit'
   s.osx.framework = 'AppKit'
   s.dependency 'AppCheckCore', '~> 11.0'
-  s.dependency 'AppAuth', '>= 1.7.3', '< 2.0'
-  s.dependency 'GTMAppAuth', '>= 4.1.1', '< 5.0'
+  s.dependency 'AppAuth', '~> 2.0'
+  s.dependency 'GTMAppAuth', '~> 5.0'
   s.dependency 'GTMSessionFetcher/Core', '~> 3.3'
   s.resource_bundle = {
     'GoogleSignIn' => ['GoogleSignIn/Sources/{Resources,Strings}/*']

Package.swift

@@ -44,15 +44,15 @@ let package = Package(
     .package(
       name: "AppAuth",
       url: "https://github.com/openid/AppAuth-iOS.git",
-      from: "1.7.3"),
+      from: "2.0.0"),
     .package(
       name: "AppCheck",
       url: "https://github.com/google/app-check.git",
       from: "11.0.0"),
     .package(
       name: "GTMAppAuth",
-      url: "https://github.com/google/GTMAppAuth.git",
-      from: "4.1.1"),
+      url: "https://github.com/brnnmrls/GTMAppAuth.git",
+      from: "5.0.0"),
     .package(
       name: "GTMSessionFetcher",
       url: "https://github.com/google/gtm-session-fetcher.git",