Artificact file name collisions in end2end-tests workflow.

[peterwilsoncc]

Description

Each of the runs in the E2E workflow use the same file names for uploading artifacts:

• failures-artifacts
• flaky-tests-report

In the event multiple runs in the workflow fail, this results in errors on the GitHub action:

Error: Failed to CreateArtifact: Received non-retryable error: Failed request: (409) Conflict: an artifact with this name already exists on the workflow run

Step-by-step reproduction instructions

1. Go to https://github.com/WordPress/gutenberg/actions/runs/7896354080/job/21550242344
2. View the Playwright 6 log
3. The failed tests will show the error above.

Screenshots, screen recording, code snippet

Screenshot in case the logs go missing.

Environment info

GitHub, Gutenberg Trunk.

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes

[Mamaduka]

We can probably use the pattern suggested here - actions/upload-artifact#478.