fix: allow setting of inherited ref table columns. closes #3670

[chinook25]

closes #3670

What are the main changes you did:

• fix Unable to Save Multiple Treatments (extends) for a Subject (using refback to treatment) #3670

how to test:
1:

• See issue

2:

• Go to the schema editor (of the test schema in the issue)
• Go to Rasopathies
• Edit diabetesTreatment
• See that you can select a ref-column (before the fix it said 'No options provided'

todo:

• updated docs in case of new feature
• added/updated tests
• added/updated testplan to include a test for this fix, including ref to bug using # notation

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
75.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud