Avoid bundling duplicate libmathcat_py.pyd (#20081)
Closes #20046
Summary of the issue:
libmathcat_py.pyd is created both in the NVDA installation directory and in include\nvda-mathcat\assets.
Description of user facing changes:
Reduces the size of the launcher by ~4 MB.
Description of developer facing changes:
None; libmathcat_py can still be imported the same way. The duplicate being removed was not imported or used by any other code.
Description of development approach:
Excludes importable files in the same way that is already used for synthDrivers on line 389 of setup.py.
