HPCC-11002 Add FROMXML examples to the regression suite

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #5520 from ghalliday/issue11002

HPCC-11002 Add FROMXML examples to the regression suite

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>