Remove --fatal-infos from dart pub downgrade analysis (dart-archive/web_socket_channel#367)

Author: brianquinlan

pkgs/web_socket_channel/.github/workflows/test-package.yml

@@ -68,4 +68,4 @@ jobs:
       - uses: actions/checkout@44c2b7a8a4ea60a981eaca3cf939b5f4305c123b
       - uses: dart-lang/setup-dart@f0ead981b4d9a35b37f30d36160575d60931ec30
       - run: dart pub downgrade
-      - run: dart analyze --fatal-infos
+      - run: dart analyze