Add manual confirmation on manual job

Add manual confirmation modal on manual job with `manual_confirmation keyword

Connected to Confirmation for manual CI actions

FE for !148778 (merged)

What does this MR do and why?

MR acceptance checklist

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Screenshots or screen recordings

How to set up and validate locally

# .gitlab-ci.yml

job1:
  script: echo

job2:
  script: echo

manual-job1:
  script: echo
  rules:
    - if: $VAR == null
      when: manual
  manual_confirmation: 'here is my confirmation message 1'

manual-job2:
  script: echo
  when: manual
  manual_confirmation: 'here is my confirmation message 2'

Test manual action on the following page

• Pipeline tab in the Merge Request page
• Pipeline tab in the Create Merge Request page
• Commit page
• Pipeline details page
• Jobs tab in the pipelines page
• Pipelines table in Build -> Page