Merge branch '519957-bulk-embedding-preprocessor' into 'master'

ActiveContext preprocessor for embeddings

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/183693



Merged-by: Madelein van Niekerk <mvanniekerk@gitlab.com>
Approved-by: Dmitry Gruzd <dgruzd@gitlab.com>
Reviewed-by: GitLab Duo <gitlab-duo@gitlab.com>