Add govern and manage stages for automatically running e2e:package-and-test-ee job

What does this MR do and why?

This is a follow up of !133825 (merged)

Related issue: gitlab-org/quality/quality-engineering/team-tasks#1472

For MRs with devopsgovern and devopsmanage labels

1. Roll out automatic selective test execution (when MR is approved)
2. Disable positing message that asks to manually run the trigger-omnibus-and-follow-up-e2e

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Before	After

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

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