- make unit tests more e2e
- use runtime_data to store connection

- added better type safety for Deako config entries
- refactored the config flow tests to use a conftest mock instead of directly patching
- removed pytest.mark.asyncio test decorators

- simplify config entry type
- add test for single_instance_allowed
- remove light.py get_state(), only used once, no need to be separate function

Co-authored-by: Joost Lekkerkerker <joostlek@outlook.com>