Provide option for cleaning up files that PipReport produces

[pauld-msft]

It appears that the pip install command that runs during PipReport will produce some artifacts that are not cleaned up at the end of the run. Some examples of these:

• .egg-info/ directories https://setuptools.pypa.io/en/latest/deprecated/python_eggs.html#eggs-and-their-formats
• .egg files
• __pycache__/ directories https://pip.pypa.io/en/stable/topics/caching/

It would be valuable for some customers to have the option to remove all files that are produced, leaving the source as it was found.