HPCC-9250 XPATH can no longer be ambiguous

Signed-off-by: RichardTaylorHPCC <richard.taylor@lexisnexis.com>
Merge pull request #4811 from RichardTaylorHPCC/B9250

HPCC-9250 XPATH can no longer be ambiguous

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>