subscribe_state excessive buffering

[ducky64]

Running the example 'subscribe to state changes', while the connect and device info returns pretty fast, once subscribe_state is called, it tends to buffer for ~20s before returning bunch of state updates at once.

This seems to happen when the ESPHome device is streaming data frequently. When there is less frequent data sent (say, only one sensor with a 3s update time), the delay becomes very short.

This happens on Windows 10, Windows 11, and WSL in Windows 10 (though in WSL, the buffering time is lower, but still quite significant). There seems to be no perceptible buffer delay in Linux (as a virtual machine on a Windows 10 host).

[bdraco]

fixed by #932 but needs python to support it in python/cpython#123478