HPCC-11783 Return NodeGroup in WUInfo ECLResult

The WsWorkunits/WUInfo is updated to return 'NodeGroup'
inside the ECLResult when the result has a 'logicalName'.

Signed-off-by: wangkx <kevin.wang@lexisnexis.com>
I am concerned if this, via WsWuInfo::getResult, is called a lot.
getEnvironmentThorClusterNames/getEnvironmentHThorClusterNames walks over all clusters/instances in environment.

@GordonSmith - are calls to WsWuInfo::getResult going to be one-off or might client call for 100's of results?