When a job needs not run, make it manual

What does this MR do and why?

When we need to skip an e2e test job in dynamic child pipelines, make the job manual instead of not creating it at all. This will allow optionally triggering of these jobs in pipelines where only the jobs related to the devops label will be automatically run.

Related to: https://gitlab.com/gitlab-org/quality/team-tasks/-/issues/1287

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