Firestore: use unique collection names in integration tests

[dconeybe]

Fix some Firestore integration tests to use uniquely-generated collection names rather than hardcoding the collection names. This ensures that concurrently-executing tests will not interfere with each other.

There have recently been a few flakes, such as in the supports partials with merge test that could be explained by concurrently-executing tests both manipulating the same collection. By uniquely generating the collection ID this possibility is eliminated.

[changeset-bot]

⚠️ No Changeset found

Latest commit: e071468

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[google-oss-bot]

Size Report ¹

Affected Products

No changes between base commit (41f06be) and merge commit (abd1216).

Test Logs

• Base (41f06be): https://github.com/firebase/firebase-js-sdk/actions/runs/4745069000
• Merge (abd1216): https://github.com/firebase/firebase-js-sdk/actions/runs/4745140441

1. https://storage.googleapis.com/firebase-sdk-metric-reports/1LAKae79Th.html

[google-oss-bot]

Size Analysis Report ¹

Affected Products

No changes between base commit (41f06be) and merge commit (abd1216).

Test Logs

• Base (41f06be): https://github.com/firebase/firebase-js-sdk/actions/runs/4745069000
• Merge (abd1216): https://github.com/firebase/firebase-js-sdk/actions/runs/4745140441

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