Remove statement to set the logging level

Using urllib3 as an example, users should be able to set the default level of all loggers when configuring logging instead of relying on each library to set the appropriate level.

Author: qthibeault

mavsdk/async_plugin_manager.py

@@ -31,7 +31,6 @@ async def _connect_backend(self):
         )
 
         logger = logging.getLogger(__name__)
-        logger.setLevel(logging.DEBUG)  # Enable debug messages by default
         logger.addHandler(logging.NullHandler())  # Avoid errors when user has not configured logging
 
         logger.debug("Waiting for mavsdk_server to be ready...")