Merge branch 'eread/move-audit-event-streaming-graphql-api-pages-to-api-directory' into 'master'

Move audit event streaming GraphQL API pages to api directory

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/153648



Merged-by: Suzanne Selhorn <sselhorn@gitlab.com>
Co-authored-by: Evan Read <eread@gitlab.com>