HPCC-10894 - Prevent spurious loop continuation

A global LOOP could continue on to next or continue past last
loop iteration, if the time between completeing iteration
messages from slaves was > 25 minutes

Signed-off-by: Jake Smith <jake.smith@lexisnexis.com>
Merge branch 'hpcc-10894' into candidate-4.2.4

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>