* refactor tests for KNX
- implement KNXTestKit class for convenient setup and assertion of KNX telegrams
- add fixture returning an instance of KNXTestKit with automatic cleanup test
* add tests for expose default attribute
- fix expose edge case not covered by #53046
* use asyncio.Queue instead of AsyncMock.call_args_list
for better readability
* get xknx from Mock instead of hass.data
* fix type annotations
* add injection methods for incoming telegrams
* rest read-response in expose
