HPCC-11007 Failed wildcard spray, empty directory, assert

Fix empty directory handling error.

Signed-off-by: Attila Vamos <attila.vamos@gmail.com>
HPCC-11007 Failed wildcard spray, empty directory, assert

Update after review.

Signed-off-by: Attila Vamos <attila.vamos@gmail.com>
Merge pull request #5536 from AttilaVamos/HPCC-11007-fix

HPCC-11007 Failed wildcard spray, empty directory, assert

Reviewed-By: Gavin Halliday <gavin.halliday@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>