Backend API to create Service Account User Self Managed
For Service Account Users
https://gitlab.com/groups/gitlab-org/-/epics/6777
[We are already done with Backend Service for creating users](https://gitlab.com/gitlab-org/gitlab/-/issues/392000)
This Issue for creating an API creating users of type `Service Accounts`. We may need to make changes to `POST API` call for users to handle user of type `Service Accounts`
Following API call is there for admins only and can be used for Self-managed
https://docs.gitlab.com/ee/api/users.html#user-creation
issue