HPCC-9073 Report better error for unsupported DISTRIBUTION types

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #6549 from ghalliday/issue9073

HPCC-9073 Report better error for unsupported DISTRIBUTION types

Reviewed-By: Jamie Noss <james.noss@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>