tests: Change docstring for CopyLinkTestCase

Change-Id: Ic31b8073090abffe4e90cd208b684e99b83d7ef2
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/358455
Tested-by: Gavin Mak <gavinmak@google.com>
Commit-Queue: Gavin Mak <gavinmak@google.com>
Reviewed-by: Josip Sokcevic <sokcevic@google.com>

tests/test_project.py

diff --git a/tests/test_project.py b/tests/test_project.py
index 66c05f6..c50d994 100644
--- a/tests/test_project.py
+++ b/tests/test_project.py
@@ -106,7 +106,7 @@
 class CopyLinkTestCase(unittest.TestCase):
   """TestCase for stub repo client checkouts.
 
-  It'll have a layout like:
+  It'll have a layout like this:
     tempdir/          # self.tempdir
       checkout/       # self.topdir
         git-project/  # self.worktree