[Bug]: Removing a Testset that is referenced by an Evaluation Model causes an Internal Server Error

[aybruhm]

Describe the bug
When you remove a testset that is in use by an evaluation, it causes an internal server error when you go to the evaluation page.

To Reproduce
Steps to reproduce the behavior:

1. Create any evaluation with any testset of your choice
2. Navigate to the testset page, and delete the testset that is in use
3. Navigate to the evaluations page, you'll get: "Internal Server Error"

Expected behavior
A modal should be displayed that tells users that deleting the testset will change the testset to a dummy testset in the evaluation using the testset being deleted.

[mmabrouk]

• We have decided to solve this issue by disallowing users to remove testsets used by evaluations.
• The expected behavior is show a modal letting the users know that they cannot do this action unless they remove a certain list of evaluations