This was causing the test script to fail to find angleutil.

Bug: angleproject:5133
Change-Id: I621da4e71c0b61161694d95263b7dad643a728ed
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3015516
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Tim Van Patten <timvp@google.com>