Resolve "Auto stop environments after a certain period"

What does this MR do?

This implements the front-end for #20956 (closed), with the backend in !19931 (merged). That is, it adds the ability to view and cancel auto-stop times for environments on the environment table and environment detail page.

Testing locally

To test locally, create a project with a .gitlab-ci.yml that includes an auto_stop_in key and then run the pipeline. auto_stop_in accepts valuse like 20 minutes or 2 days.

Example:

review:
  script: echo 'a'
  environment:
    name: review/$CI_COMMIT_REF_SLUG
    auto_stop_in: 2 days
    on_stop: stop_review

stop_review:
  script: echo 'a'
  environment:
    name: review/$CI_COMMIT_REF_SLUG
    action: stop
  when: manual

Screenshots

	environments table	environment detail
before
after
after
after

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers