BUG/MINOR: stop connect timeout when connect succeeds

BUG/MINOR: stop connect timeout when connect succeeds

If the connect succeeds exactly at the same millisecond as the connect
timeout is supposed to strike, the timeout is still considered while
data may have already be sent. This results in a new connection attempt
with no data and with the response being lost.

Note that in practice the only real-world situation where this is observed
is when connect timeouts are extremely low, too low for safe operations.
This bug was encountered with a 1ms connect timeout.

It is also present on 1.4 and needs to be fixed there too.