HPCC-12107 Segmentation fault when supplying an incorrect Wuid

Fix build break.

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #6393 from richardkchapman/build-break-nulltext

HPCC-12107 Segmentation fault when supplying an incorrect Wuid

Reviewed-By: Jake Smith <jake.smith@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>