prep for 2.8
Fix query cookies not being inside VCS directories

Summary: Stupid mistake.

Test Plan: `arc unit --everything` with the added test

Reviewers: wez

Reviewed By: wez

Differential Revision: https://phabricator.fb.com/D909339

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extra : rebase_source : 2dd54aa2d7745b39a1692faafbf32c04dbaa1fba