Investigate if the SLEEP is necessary in emulator after each action

[grdddj]

Find out if we really need to sleep for half a second after each action with emulator - or if we can get rid of it, or at least decrease the time.

Explanation of the sleep interval (done by unknown person):

trezor-user-env/src/emulator.py

Lines 24 to 28 in b7ddfa9

	# When communicating with device via bridge/debuglink, this sleep is required
	# otherwise there may appear weird race conditions in communications.
	# When not going through bridge but webusb, there is no need for it,
	# but we can skip bridge only when doing initial setup before test.
	SLEEP = 0.501

This long sleep causes some issue in trezor/trezor-suite#4066