Add pywin32 for Windows platform

[JarryShaw]

Trying to fix the following dependency issue on Windows platform 😄

>>> import osquery
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Users\fakepath\AppData\Local\Programs\Python\Python37\lib\site-packages\osquery\__init__.py", line 34, in <module>
    from osquery.extension_client import DEFAULT_SOCKET_PATH, ExtensionClient, \
  File "C:\Users\fakepath\AppData\Local\Programs\Python\Python37\lib\site-packages\osquery\extension_client.py", line 25, in <module>
    from osquery.TPipe import TPipe
  File "C:\Users\fakepath\AppData\Local\Programs\Python\Python37\lib\site-packages\osquery\TPipe.py", line 11, in <module>
    import win32event
ModuleNotFoundError: No module named 'win32event'

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ Jarry Shaw (4f2eaf5, 9ebab7e)