Tidy up a test.

Change-Id: I0d5bca1b9915fa5485d4b01796a276959788f427
Reviewed-on: https://code-review.googlesource.com/c/re2/+/50410
Reviewed-by: Paul Wankadia <junyer@google.com>
(cherry picked from commit 85c014206aee9bc1730dc416b33609974ae3ff5f)
Reviewed-on: https://code-review.googlesource.com/c/re2/+/50411
1 file changed