[Feature flag] Cleanup check_membership_in_protected_ref_access

Pranav Jainrequested to merge
nav-remove-feature-flag into master

What does this MR do and why?

Prevent deploy key access when owner is not a member of the project

Clean up the check_membership_in_protected_ref_access feature flag

Changelog: fixed

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

Before After

How to set up and validate locally

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

Merge request reports