v0.3.0-beta.1

This is the first version of the integration that changes the core components of the integration to async, thus we jump to a new "major" version. Please provide feedbacks on this beta since the changes are quite deep.

Changelog:

• Moves pyopnsense and coordinator to async to reduce blocking
  • Can likely optimize the entity classes as well in a future PR
• Change from requests to aiohttp for GET and POST calls
  • XMLRPC remains not threadsafe. There are a couple of async/aio versions but I'm not sure how maintained they are.
• Move coordinator to its own file
• Move dict_get to helpers file
• Add more typing hints and annotations
• Standardized case everywhere to be OPNsense
• Improved logging and error messages