Pick 10.2.4 security fixes into master

See merge request gitlab-org/gitlab-ce!15821

(cherry picked from commit 1eff1bd3)

d332c8c7 Merge branch '36679-non-authorized-user-may-see-wikis-or-pipeline-page' into 'security-10-2'
8c0aa7d4 Merge branch 'bvl-10-2-email-disclosure' into 'security-10-2'
8f29d264 Merge branch 'rs-security-group-api' into 'security-10-2'
c59ae547 Merge branch 'issue_30663' into 'security-10-2'
f4fbe61a Merge branch 'note-preview' into 'security-10-2'
0f811675 Manually add 10.2.4 changelog entries
f71e48a0 Resolve conflicts in app/models/user.rb