HPCC-10188 Rename Properties to attributes for consistency

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #4971 from ghalliday/issue10188

HPCC-10188 Rename Properties to attributes for consistency

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>