fix(auth,messaging): package compatibility

[diegogarciar]

Description

This check ensures that firebase_auth only handles remoteNotifications when firebase_messaging is not present, when firebase_messaging is present, it will send auth messages to firebase_auth.

Related Issues

Fixes #4097
Fixes #4412
Fixes #4388

Checklist

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This will ensure a smooth and quick review process. Updating the pubspec.yaml and changelogs is not required.

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• My PR includes unit or integration tests for all changed/updated/fixed behaviors (See Contributor Guide).
• All existing and new tests are passing.
• I updated/added relevant documentation (doc comments with ///).
• [-] The analyzer (flutter analyze) does not report any problems on my PR.
• I read and followed the Flutter Style Guide.
• I signed the CLA.
• I am willing to follow-up on review comments in a timely manner.

-flutter analyze
warning • The include file package:pedantic/analysis_options.1.8.0.yaml in
/Users/diego/Documents/flutterfire/analysis_options.yaml cannot be found • analysis_options.yaml:1:11 •
include_file_not_found
warning • The include file package:pedantic/analysis_options.1.8.0.yaml in
/Users/diego/Documents/flutterfire/analysis_options.yaml cannot be found • analysis_options.yaml:1:11 •
include_file_not_found

Breaking Change

Does your PR require plugin users to manually update their apps to accommodate your change?

• Yes, this is a breaking change (please indicate a breaking change in CHANGELOG.md and increment major revision).
• No, this is not a breaking change.