Error if HA endpoint configuration is missing in configuration.yaml

[ssenart]

If the following configuration parameter is missing:

homeassistant::
  endpoint: "/api/websocket"

We have the error:

2025-01-15 18:43:52 ERROR [gazpar2haws.__main__] An error occured while running Gazpar2HAWS: Traceback (most recent call last):
  File "c:\Users\steph\Qsync\Workspace\Python\gazpar2haws\gazpar2haws\__main__.py", line 87, in main
    await bridge.run()
  File "c:\Users\steph\Qsync\Workspace\Python\gazpar2haws\gazpar2haws\bridge.py", line 59, in run
    await self._homeassistant.connect()
  File "c:\Users\steph\Qsync\Workspace\Python\gazpar2haws\gazpar2haws\haws.py", line 34, in connect
    self._websocket = await websockets.connect(
                      ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "c:\Users\steph\Qsync\Workspace\Python\gazpar2haws\.venv\Lib\site-packages\websockets\asyncio\client.py", line 442, in __await_impl__
    self.connection = await self.create_connection()
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "c:\Users\steph\Qsync\Workspace\Python\gazpar2haws\.venv\Lib\site-packages\websockets\asyncio\client.py", line 347, in create_connection
    wsuri = parse_uri(self.uri)
            ^^^^^^^^^^^^^^^^^^^
  File "c:\Users\steph\Qsync\Workspace\Python\gazpar2haws\.venv\Lib\site-packages\websockets\uri.py", line 84, in parse_uri
    port = parsed.port or (443 if secure else 80)
           ^^^^^^^^^^^
  File "C:\Program Files\Python312\Lib\urllib\parse.py", line 182, in port
    raise ValueError(f"Port could not be cast to integer value as {port!r}")
ValueError: Port could not be cast to integer value as '6123None'

We don't want that and have to set a default value for that missing parameter.