HPCC-9819 Fix build break in windows caused by HPCC-9789

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #4722 from ghalliday/issue9819

HPCC-9819 Fix build break in windows caused by HPCC-9789

Merged following review by Jake
Merge remote-tracking branch 'origin/candidate-4.0.2'

Merged-by: Gavin Halliday <ghalliday@hpccsystems.com>