Merge branch 'seperate-project-and-group-integrations-api-document' into 'master'

Split Project integrations and Group integrations document

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/181993



Merged-by: Ashraf Khamis <akhamis@gitlab.com>
Approved-by: Ashraf Khamis <akhamis@gitlab.com>
Reviewed-by: Ashraf Khamis <akhamis@gitlab.com>
Co-authored-by: Rez <rmarandi@gitlab.com>