HPCC-11078 Generate isRightAlreadySorted for global joins

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #5611 from ghalliday/issue11078

HPCC-11078 Generate isRightAlreadySorted for global joins

Reviewed-By: Jamie Noss <james.noss@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>