false positive related object in custom fields

[opericgithub]

Deployment Type

Self-hosted

NetBox Version

v3.7.4

Python Version

3.10

Steps to Reproduce

1. Create new custom field.
2. Try to delete the newly created custom field.
3. There is a message that the related object "CustomField_content_types object (n)" will also get deleted.

Expected Behavior

Newly created custom field isn't bound to any object, so user should get simple delete confirmation dialog without related objects.

Observed Behavior

User gets delete confirmation dialog with related objects even though those kinds of objects don't exist.

Another observation, don't know if it is this issue related:
During the upgrade procedure to the feature branch, I get the following error mentioning the customfield_content_types:

File "/opt/netbox/venv/lib/python3.10/site-packages/psycopg/cursor.py", line 732, in execute
    raise ex.with_traceback(None)
django.db.utils.ProgrammingError: relation "extras_customfield_content_types_id_seq" does not exist

[DanSheps]

User gets delete confirmation dialog with related objects even though those kinds of objects don't exist.

This is not that it is bound to a specific object, it is just stating that the custom field has a relation to the django content type table.

Technically, it is not incorrect, but I agree we should probably exempt the contenttype field from the relationship check on deletion, at least for this specific case.

[Julio-Oliveira-Encora]

Could you please assign it to me?