[17.0] Weird behaviour for referenced tests

[arielbarreiros96]

Module

quality_control_oca

Describe the bug

Once the quality_control_oca without doing any sort of configuration, the object_id fields behaves in a non desirable way.

To Reproduce

17.0 and 18.0: I've tested only 17.0 and 18.0, the problem could be affecting other versions, but I cannot confirm nor deny.

Steps to reproduce the behavior:

1. Install quality_control_oca only
2. Navigate to Tests->Tests and create a new Test
3. Change the type to "Related"
4. Check the object_id ("Reference object") field possible values, the possible values correspond to the "set()" string

Expected behavior
According to readme, it should be possible to create test of type related, however with this bug seems impossible to do so. I feel more natural to create general ones and then assign the relation at inspection level, in any case with bug renders the Related type unusable

Additional context
I happened in runboat and clean local install