Apply labels and trigger a new pipeline for qa only changes

What does this MR do and why?

Apply labels and trigger a new pipeline for qa only changes

Originally we don't want to trigger a new pipeline from !1133 (merged)

Because the minimal pipelines already run the following jobs:

• qa:internal (still true)
• qa:selectors (still true)
• package-and-qa (now it's false)

However now we no longer run any E2E tests on minimal pipelines (before approval), so this is unexpected.

Now we still apply pipeline:mr-approved and pipelinetier-3 and similar labels and trigger a new pipeline for them, so that we run E2E tests for the QA changes.

Refs gitlab-org/gitlab!157453 (comment 1969124072)

Expected impact & dry-runs

These are strongly recommended to assist reviewers and reduce the time to merge your change.

See https://gitlab.com/gitlab-org/quality/triage-ops/-/tree/master/doc/scheduled#testing-policies-with-a-dry-run on how to perform dry-runs for new policies.

See https://gitlab.com/gitlab-org/quality/triage-ops/-/blob/master/doc/reactive/best_practices.md#use-the-sandbox-to-test-new-processors on how to make sure a new processor can be tested.

Action items

• If adding environment variables for reactive processors, update config/triage-web.yaml and .gitlab/ci/triage-web.yml
• (If applicable) Add documentation to the handbook pages for Triage Operations =>
• (If applicable) Identify the affected groups and how to communicate to them:
  • /cc @person_or_group =>
  • Relevant Slack channels =>
  • Engineering week-in-review