issue templates: require to disable 'users can request access'

This shouldn't be possible as it may lead to accidentally allowing
external users to be added to a project.
We should only add members to a project or group on staff request to
devops.

.gitlab/issue_templates/New Official Project.md

@@ -39,6 +39,8 @@ If you want to add a new official project, here are some guidelines to follow:
 1. [ ] The *Protected Branches* in https://gitlab.archlinux.org/archlinux/my-example/-/settings/repository should specify
        `Allowed to merge` and `Allowed to push` as `Developers + Maintainers.`
 1. [ ] Disable unneeded project features under *Visibility, project features, permissions* (https://gitlab.archlinux.org/archlinux/my-example/edit)  
+   Always:
+   - `Users can request access`: `off`  
    Often, but not always:
    - Repository -> Container registry
    - Repository -> Git Large File Storage (LFS)