Merge branch 'vij-add-last-activity-on-members' into 'master'

Adds last_activity_on to Members table

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/153593



Merged-by: Omar Qunsul <oqunsul@gitlab.com>
Approved-by: Dominic Bauer <dbauer@gitlab.com>
Approved-by: Omar Qunsul <oqunsul@gitlab.com>
Co-authored-by: Vijay Hawoldar <vhawoldar@gitlab.com>