[gsi_web] Update CHANGELOG and version.

Author: ditman

packages/google_sign_in/google_sign_in_web/CHANGELOG.md

@@ -1,3 +1,12 @@
+## 0.12.1
+
+* Enables FedCM on browsers that support this authentication mechanism.
+* Uses the expiration timestamps of Credential and Token responses to improve
+  the accuracy of `isSignedIn` and `canAccessScopes` methods.
+* Deprecates `signIn()` method.
+  * Users should migrate to `renderButton` and `silentSignIn`, as described in
+    the README.
+
 ## 0.12.0+5
 
 * Migrates to `dart:ui_web` APIs.

packages/google_sign_in/google_sign_in_web/pubspec.yaml

@@ -3,7 +3,7 @@ description: Flutter plugin for Google Sign-In, a secure authentication system
   for signing in with a Google account on Android, iOS and Web.
 repository: https://github.com/flutter/packages/tree/main/packages/google_sign_in/google_sign_in_web
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+google_sign_in%22
-version: 0.12.0+5
+version: 0.12.1
 
 environment:
   sdk: ">=3.1.0 <4.0.0"