HPCC-11496 - 2nd attempt at avoiding contention on ClusterLock

Signed-off-by: Jake Smith <jake.smith@lexisnexis.com>
Merge pull request #6067 from jakesmith/hpcc-11496b

HPCC-11496 - 2nd attempt at avoiding contention on ClusterLock

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>