Fix multiline comment formatting

Many incorrectly formatted comments exist from the switch to
4 space indent: https://crrev.com/c/4836379

Bug: 1514505
Change-Id: I6366f9da812919bd35b999f18fa8a49b7a66c09b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/5153633
Commit-Queue: Gavin Mak <gavinmak@google.com>
Reviewed-by: Josip Sokcevic <sokcevic@chromium.org>

tests/presubmit_canned_checks_test.py

@@ -344,8 +344,8 @@ class DescriptionChecksTest(unittest.TestCase):
 class ChromiumDependencyMetadataCheckTest(unittest.TestCase):
     def testDefaultFileFilter(self):
         """Checks the default file filter limits the scope to Chromium dependency
-    metadata files.
-    """
+        metadata files.
+        """
         input_api = MockInputApi()
         input_api.change.RepositoryRoot = lambda: ''
         input_api.files = [