REGTESTS: make tcp-check_min-recv fail fast

REGTESTS: make tcp-check_min-recv fail fast

This test was dependent on the check/server timeout to detect a failure,
which is not logical since we also use that one as an upper bound for
success in the second test, and that needlessly extends the test duration.
Let's make sur the timeout strikes immediately with only 1 ms timeout. Now
the total tests time is around 5.3-5.4s down from 8.7s in dev14. There is
still quite some room for improvement in the peers tests which all wait 2s
before starting but this will be more complicated.