HPCC-10839 New ECL Watch Deselection broken

Deselected items would still show up in selections.
Deleted items would still be in selection list.

Fixes HPCC-10839

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>
Merge pull request #5411 from GordonSmith/HPCC-10839

HPCC-10839 New ECL Watch Deselection broken

Reviewed-By: Kevin Wang <kevin.wang@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>