auth: Support latest google_cloud, prepare release (#735)

googleapis_auth/CHANGELOG.md

diff --git a/googleapis_auth/CHANGELOG.md b/googleapis_auth/CHANGELOG.md
index 7a08889..5d76e91 100644
--- a/googleapis_auth/CHANGELOG.md
+++ b/googleapis_auth/CHANGELOG.md
@@ -1,4 +1,6 @@
-## 2.2.1-wip
+## 2.2.1
+
+- Require `google_cloud: '>=0.3.0 <0.5.0'`
 
 ## 2.2.0
 

googleapis_auth/pubspec.yaml

diff --git a/googleapis_auth/pubspec.yaml b/googleapis_auth/pubspec.yaml
index dc29e5c..601fd04 100644
--- a/googleapis_auth/pubspec.yaml
+++ b/googleapis_auth/pubspec.yaml
@@ -1,5 +1,5 @@
 name: googleapis_auth
-version: 2.2.1-wip
+version: 2.2.1
 description: Obtain Access credentials for Google services using OAuth 2.0
 repository: https://github.com/google/googleapis.dart/tree/master/googleapis_auth
 
@@ -9,7 +9,7 @@
 
 dependencies:
   crypto: ^3.0.0
-  google_cloud: ^0.3.0
+  google_cloud: '>=0.3.0 <0.5.0'
   google_identity_services_web: ^0.3.3
   http: ^1.2.2
   http_parser: ^4.0.0