HPCC-12174 Build may fail due to missing esp.hpp

Depending on the order in which things build...

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #6415 from richardkchapman/intermittent-build-error

HPCC-12174 Build may fail due to missing esp.hpp

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>