git cl: Ensure update before checking if "full" format.

We found that in the bot environment sometimes we'd check the
full format setting before doing a lazy config update. Adds an
explicit call to ensure the lazy update. Fixes the problem of
the bot environment not running the same format checks in some
cases.

Bug: 1219863
Change-Id: I970d97da462972300f52cbcb382f7da3929b73e6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3009534
Auto-Submit: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Dirk Pranke <dpranke@google.com>
Reviewed-by: Dirk Pranke <dpranke@google.com>

git_cl.py

@@ -826,6 +826,7 @@ class Settings(object):
 
   def GetFormatFullByDefault(self):
     if self.format_full_by_default is None:
+      self._LazyUpdateIfNeeded()
       result = (
           RunGit(['config', '--bool', 'rietveld.format-full-by-default'],
                  error_ok=True).strip())