HPCC-11741 WUDetails Helper Count is calculated at the wrong time/place

Fixes HPCC-11741

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>
Merge pull request #6350 from GordonSmith/HPCC-11741

HPCC-11741 WUDetails Helper Count is calculated at the wrong time/place

Reviewed-By: Miguel Vazquez <miguel.vazquez@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>