The Test Run details cannot open after the associated pre-condition was deleted

The Test Run details cannot open after the associated pre-condition gets removed.

How to reproduce:

1. Create a Pre-condition
2. Create a Test and associate the Pre-condition
3. Create a Test Execution and run the Test
4. Delete the Pre-condition
5. Go to the Test Execution and open the Execution Details

It returns an error and does not show the Test Run detail anymore.

Expected result
The testrun page should show the banner asking for the user to either reset, merge or do nothing about the changes on the test and precondition being reflected in the testrunpage.