Renaming a group removes any associated submissions

[donny-wong]

The following scenario will remove associated submissions when renaming the group for an assignment:

Pre-requisites: An existing assignment where a group was created and renamed.
(An existing example: the aaaautotest group for the prep02 assignment -- their repo is group_004)

Steps to reproduce:

1. In another assignment, create a group (this was group_3390)

2. Add a submission to that group, collect, and run tests

3. Rename the group (i.e. in this case, renamed group_3390 to aaaautotest)

4. The renamed group's repository will now point to the one from the other assignment (i.e. the repo has changed from group_3390 to group_004). A few results of this:

   • The submission will never be able to find the associated file
   • But the automated test results will still be there

Note: If the group was renamed to a non existent group, it won't switch repositories.