Add period below review URL when adding review URL footer to committed CLs

Because some interfaces aren't linkifying the URL when the commit message ends with it.

BUG=480922
TESTED=tests/git_cl_test.py; presubmit ok

Review URL: https://codereview.chromium.org/1165293002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@295566 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/tests/git_cl_test.py b/tests/git_cl_test.py
index 54878eb..cb87bdb 100755
--- a/tests/git_cl_test.py
+++ b/tests/git_cl_test.py
@@ -359,7 +359,7 @@
       ((['git', 'reset', '--soft', 'fake_ancestor_sha'],), ''),
       ((['git', 'commit', '-m',
          'Issue: 12345\n\nR=john@chromium.org\n\n'
-         'Review URL: https://codereview.example.com/12345'],),
+         'Review URL: https://codereview.example.com/12345.'],),
        ''),
       ((['git', 'config', 'rietveld.force-https-commit-url'],), ''),
       ((['git',