CI/CD a11y label fixes

What does this MR do and why?

Fixes some CI/CD a11y label violations

Picked fixes from A11y audit: Accessible name missing (!181288 - closed) for the CI/CD area

References

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Screenshots or screen recordings

How to set up and validate locally

1. Enable FF echo "Feature.enable(:ci_job_assistant_drawer)" | rails c
2. Go to http://gdk.test:3000/flightjs/Flight/-/ci/editor, Click on Job assistent
3. Go to http://gdk.test:3000/flightjs/Flight/-/ci/editor?branch_name=master&tab=2
4. Go to http://gdk.test:3000/flightjs/Flight/-/pipeline_schedules/new
5. Go to http://gdk.test:3000/flightjs/Flight/-/pipelines/new

Related to #512691 (closed)

Closes https://gitlab.com/gitlab-org/gitlab/-/issues/511835