Created by: jiangty-addepar
This PR deletes the remaining dead code relating to buck test --dry-run.
https://github.com/facebook/buck/commit/4ea890754b5612c41cacf6a94d089a3960282e40 was an incomplete un-revert of https://github.com/facebook/buck/commit/b5f4e756a922c74b1e3d8fad7ba9d704dfd2f771.
Test Plan: buck test.