Merge branch 'vij-cleanup-track-member-activity' into 'master'

Remove track_member_activity feature flag

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/176480



Merged-by: Vijay Hawoldar <vhawoldar@gitlab.com>
Approved-by: david hamp-gonsalves <dhamp-gonsalves@gitlab.com>
Approved-by: Smriti Garg <sgarg@gitlab.com>