Issue #3109556 by finnsky, nod_, longwave, effulgentsia, Ambient.Impact: Update from Yarn 1 to Yarn 4

Issue #3240792 by justafish, alexpott, andypost, smustgrave, longwave: Use lullabot/mink-selenium2-driver and lullabot/php-webdriver for functional browser testing

Issue #3419182 by longwave: Test-only job fails with "couldn't find remote ref refs/heads/11.x" when 11.x branch does not exist in fork

Issue #3402061 by fjgarlin, alexpott, smustgrave, catch, longwave: Disable DNS prefetch in Chromedriver on gitlabci

Issue #3401047 by Spokje, longwave, smustgrave, fjgarlin: Nightwatch output on GitLab not easily readable

Issue #3412415 by larowlan, fjgarlin, longwave, drumm, benjifisher: Make CI template compatible with private repositories

Issue #3408073 by mstrelan, fjgarlin: Test-only job from parent pipeline skips Functional Javascript tests

Issue #3405242 by fjgarlin: GitLab CI pods load too high when running multiple pipelines at the same time

Issue #3385621 by fjgarlin, andypost, dimitriskr, longwave: [GitlabCI] MariaDB currently not working

Issue #3395977 by fjgarlin, smustgrave, mstrelan, mondrake: Test-only changes reverts changes to test modules

Issue #3401971 by fjgarlin: Test-only job shouldn't require constant rebases to detect which files were changed

Issue #3401971 by fjgarlin: Test-only job shouldn't require constant rebases to detect which files were changed

Issue #3391689 by catch, alexpott, smustgrave: Add a performance tests job to gitlab and send data to OpenTelemetry

Issue #3393475 by fjgarlin, catch: Enable running the same test multiple times on gitlab ci for random test failures

Issue #3388952 by catch, fjgarlin: Tweak gitlab CI concurrency, parallelism and test running order for 11 minute test runs

Issue #3386566 by larowlan, fjgarlin, smustgrave, catch: Add support for 'test only' changes to gitlab CI

Issue #3390073 by catch, fjgarlin: Use 'needs' instead of 'dependencies' to speed up gitlab CI jobs and run phpstan first