Add firefox cross browser test to changed packages

[dwyfrequency]

Add Firefox browser to karma and create github action to run tests across Chrome and Firefox.

[changeset-bot]

⚠️ No Changeset found

Latest commit: e85dda5

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

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[google-oss-bot]

Size Report ¹

Affected Products

No changes between base commit (f5426a5) and merge commit (1156211).

Test Logs

• Base (f5426a5): https://github.com/firebase/firebase-js-sdk/actions/runs/2751634733
• Merge (1156211): https://github.com/firebase/firebase-js-sdk/actions/runs/2755739606

1. https://storage.googleapis.com/firebase-sdk-metric-reports/0hYEab8CrB.html

[google-oss-bot]

Size Analysis Report ¹

Affected Products

No changes between base commit (f5426a5) and merge commit (1156211).

Test Logs

• Base (f5426a5): https://github.com/firebase/firebase-js-sdk/actions/runs/2751634733
• Merge (1156211): https://github.com/firebase/firebase-js-sdk/actions/runs/2755739606

1. https://storage.googleapis.com/firebase-sdk-metric-reports/YtEXSWzyHH.html