TestCase class with `ParameterCombination="sequential"` makes the whole build process hang with no error message

[ehennestad]

sphinxcontrib-matlabdomain==0.22.1

A matlab source directory contained a TestCase class with the following method attribute

methods (Test, ParameterCombination="sequential")

This caused the documentation build process to hang with no error message.

Changing the attribute keyword from a string to a char fixed it, i.e using the following instead works:

methods (Test, ParameterCombination='sequential')