HPCC-10113 - Dedup RHS if keep and no atmost/abortlimit

Can still dedup RHS with KEEP(1) as long as there is no ATMOST
or LIMIT

Signed-off-by: Jake Smith <jake.smith@lexisnexis.com>
Merge branch 'hpcc-10113b'

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