[docs] Improve `git cl patch --help`

Change-Id: I001a1baafe2b136bbe89055fec5ae91118332d1c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/4660921
Reviewed-by: Andy Perelson <ajp@google.com>
Auto-Submit: Victor Vianna <victorvianna@google.com>
Commit-Queue: Andy Perelson <ajp@google.com>
diff --git a/git_cl.py b/git_cl.py
index 41bdd7e..242bb5b 100755
--- a/git_cl.py
+++ b/git_cl.py
@@ -5206,7 +5206,7 @@
 @subcommand.usage('<patch url or issue id or issue url>')
 @metrics.collector.collect_metrics('git cl patch')
 def CMDpatch(parser, args):
-  """Patches in a code review."""
+  """Applies (cherry-picks) a Gerrit changelist locally."""
   parser.add_option('-b', dest='newbranch',
                     help='create a new branch off trunk for the patch')
   parser.add_option('-f', '--force', action='store_true',