Move docs in `project_services/` to `user/project/services/`
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Move project_services/touser/project/services/
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Move project_services/project_services.mdtouser/project/services.md
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Move services_templatestouser/admin_area/services_templates
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Submit MR to EE 
Needed for https://gitlab.com/gitlab-org/gitlab-ce/issues/21742