HPCC-12191 Reduce calls to createRowAllocator() for roxie NWayMergeJoin

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
HPCC-12206 Avoid function call if no child expression

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #6424 from ghalliday/issue12191

HPCC-12191 Reduce calls to createRowAllocator() for roxie NWayMergeJoin

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #6429 from ghalliday/issue12206

HPCC-12206 Avoid function call if no child expression

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>
HPCC-12240 Update Cassandra driver to latest

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #6440 from richardkchapman/cassandra-driver-update

HPCC-12240 Update Cassandra driver to latest

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>