Merge branch 'faleksic-master-patch-89900' into 'master'

Clarify executor for self-managed runners

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/147104



Merged-by: Russell Dickenson <rdickenson@gitlab.com>
Approved-by: Russell Dickenson <rdickenson@gitlab.com>
Co-authored-by: Filip Aleksic <faleksic@gitlab.com>