Delayed project deletion doesn't work for projects that are not in a group

Summary

Even if delayed deletion enabled at the instance level, the project delete section will show that delayed deletion is disabled on projects that are not in a group.

Steps to reproduce

1. Open Admin Area -> General -> Visibility and access controls
2. Set "Default deletion delay" to a non-zero value
3. Save changes
4. Open a project that is in a user namespace (not in a group)
5. Open Settings -> General -> Advanced
6. Locate the "Delete Project" section
7. The delete project section shows that delayed deletion is disabled.

Example Project

I have an example in a self-hosted instance. Let me know if you require access.

What is the current bug behavior?

The delete project section shows that delayed deletion is disabled. - "Delayed Project Deletion (Disabled) Projects will be permanently deleted immediately."

What is the expected correct behavior?

The delete project section shows that delayed deletion is enabled.

Relevant logs and/or screenshots

Possible fixes

If this is determined to be a bug, consider using the instance level delay setting for projects not in a group. If this is determined not to be a bug, we should clarify the documentation and UI to indicate that delayed deletion is not supported for projects not in a group.