Merge branch 'duo-chat-button' into 'master'

Add GitLab Duo Chat visibility exceptions

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/178316



Merged-by: Brendan Lynch <blynch@gitlab.com>
Approved-by: Torsten Linz <tlinz@gitlab.com>
Approved-by: Brendan Lynch <blynch@gitlab.com>
Reviewed-by: Torsten Linz <tlinz@gitlab.com>
Co-authored-by: Jonathan Glassman <jglassman@gitlab.com>