Project key / name of a deleted project can't be used in ServiceDesk.

If a JIRA Admin creates a Service Desk project and then decides to delete the project.
The admin is then unable to create a new Service Desk project that has the same name and key, even though the project is created in JIRA.
if the admin creates a project with the same name and key and then try to enable Service Desk on the project, it will not enable it.

Steps to reproduce:

1. Create a Service Desk Project.
   name: Test
   key: TES
2. Confirm that the project Exists on ServiceDesk module, and in JIRA.
3. Delete the project.
4. Try to create a new Project with the same name or key.
5. The project will be created on JIRA but the ServiceDesk can't be enable.

Expected Behaviour:

The Admin should be able to create the Service Desk after deleting.