Merge branch 'lp-docs-update-comment-and-threads-imgs' into 'master'

Updates screenshots in the Comments and threads page

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/135659



Merged-by: Amy Qualls <aqualls@gitlab.com>
Approved-by: Amy Qualls <aqualls@gitlab.com>
Co-authored-by: Lysanne Pinto <lpinto@gitlab.com>