Add feature to check only PU specific files available in a directory

[IPerezGonzalez]

I have not been able to find how to filter the files to process so that the checker only goes through the ones pertaining to a particular PU.
They only possibility I see is to loop through calls to the script/class with the files you want to process.

Would it be possible to add this feature by adding a PU filter in either the call or the json config file? This could be added to the regex that searchs for the nc files (pattern = r'.nc$')