testpilot: testpilot is broken on Sandcastle
testpilot: testpilot is broken on Sandcastle

Summary: Hack to use parexec and the par directly.

Reviewed By: chadaustin

Differential Revision: D29461444

fbshipit-source-id: 9ac6c1aa43728782b8de0a71446109f7fd5dab1d

facebook/bistro,facebook/bistro,facebook/bistro,facebook/bistro,facebook/bistro,facebook/bistro