Move FCM Integration Test off test flows

[zwu52]

Looks like part of the FCM integration test is flaky. Specifically update-token and delete-token. See below for a snippet of error message:

@firebase/messaging:   1) Firebase Messaging Integration Tests > get and delete token
@firebase/messaging:        Testing browser: Google Chrome Stable : valid-vapid-key
@firebase/messaging:          Test app can delete a valid token:
@firebase/messaging:      Error: Timeout of 100000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves. (/home/runner/work/firebase-js-sdk/firebase-js-sdk/integration/messaging/test/test-deleteToken.js)

Looking at the actions history, it looks like its affecting "test-all" and "test-modified". Moving them off workflow so that folks don't have to rerun the tests to get a green result.

[changeset-bot]

🦋 Changeset is good to go

Latest commit: 65f6f9d

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[google-oss-bot]

Binary Size Report

Affected SDKs

No changes between base commit (8e0c036) and head commit (cac6841).

Test Logs

• Base (8e0c0360): https://github.com/firebase/firebase-js-sdk/actions/runs/148905148
• Head (cac68412): https://github.com/firebase/firebase-js-sdk/actions/runs/149033578