HPCC-12128 - MP connections take too long

When A-> B and B->A within a very short time frame a 3 minute delay would often occur after which a failed connection might still occur.  This was noticed very often when using the mptests, which are used for new mp lib development.

Signed-off-by: Mark Kelly <mark.kelly@lexisnexis.com>
Yes, that is the main thrust of this fix.  Both processes are waiting for each other and we want one of them to stop.  The random numbers sent with the handshake decides who wins in this situation.