MEDIUM: quic: respect closing state even on soft-stop

MEDIUM: quic: respect closing state even on soft-stop

Prior to this patch, a special condition was set when idle timer was
rearmed for closing connections during haproxy process stopping. In this
case, the timeout was ditched and the idle task woken up immediatly.

The objective was to release quickly closing connections to not prevent
the process stopping to be too long. However, it is not conform with RFC
9000 recommandations and may cause some clients to miss a
CONNECTION_CLOSE in case of a packet loss.

A recent fix was set to use a shorter timeout for closing state. Now a
connection should only be left in this state for one second or less.
This reduces greatly the importance of stopping special condition. Thus,
this patch removes it completely.