Sort does not work within Gene Enrichment Widget

[DLWheeler]

Describe the bug
The table generated by the Gene Enrichment Widget cannot be sorted. The sorting indicators respond to mouse clicks but no sorting occurs.

To Reproduce

Provide the widget a list of gene ids, e.g. a few for Schizosaccharomyces pombe:

SPAC750.01
SPBPB21E7.04c
SPBPB21E7.01c
SPCC663.06c
SPAC869.07c
SPAC869.09
SPAC3G9.11c
SPCC663.08c
SPAC29A4.12c
SPBC609.04

Adjust Count to 2 and Pval to 0.2 to get enriched terms. The output table cannot be sorted.

Expected behavior
I expect the table to be sortable on any field.

Error message From Orange Log

2023-03-26 11:42:13,945:ERROR:resdk:
Traceback (most recent call last):
File "/Applications/Orange3.app/Contents/Frameworks/Python.framework/Versions/3.9/lib/python3.9/site-packages/orangecontrib/bioinformatics/widgets/utils/gui/init.py", line 69, in sort
return self.sourceModel().sort(*args, **kwargs)
AttributeError: 'NoneType' object has no attribute 'sort'

Desktop (please complete the following information):

• OS: [macOS 13.2.1]
• Python Version: [3.9]
• Orange Version both 3.34.0 and3.34.1
• Add-on Version [4.7.1]

Additional context
Add any other context about the problem here.

[JakaKokosar]

@DLWheeler, thanks for reporting this. I will look at it first thing tomorrow.