fix: reduce delay when stop replica #3020

[BorysTheDev]

this should fix the problem: Running replicaof no one on replica in full sync state returns after more than 20 seconds
the problem was that after we shutdown the socket the buffer still contained data and we processed it.

[dranikpg]

Please provide a description of what the problem is and what your solution does 🙂 We had similar code previously, but we chose to have a unfiied cleanup procedure because otherwise it becomes unmanageable

[dranikpg]

Actually it might be that we need just to switch those two lines 🤔

dragonfly/src/server/replica.cc

Lines 144 to 145 in 3dd6c49

	cntx_.Cancel(); // Context is fully resposible for cleanup.
	state_mask_.store(0); // Specifically ~R_ENABLED.

With this order, the loop continues working and blocks because ENABLE is still set

With an inverse order we should be cautious that nothing overrides it before cancel started