fix typo: director -> directory

Change-Id: Ic2d3ea0dbaad27aad13dcfc6cc3c4f5c1fd8c545
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/5055942
Reviewed-by: Scott Lee <ddoman@chromium.org>
Auto-Submit: Takuto Ikuta <tikuta@chromium.org>
Commit-Queue: Takuto Ikuta <tikuta@chromium.org>
Commit-Queue: Scott Lee <ddoman@chromium.org>

gclient.py

@@ -2851,7 +2851,7 @@ class Flattener(object):
 def CMDgitmodules(parser, args):
     """Adds or updates Git Submodules based on the contents of the DEPS file.
 
-  This command should be run in the root director of the repo.
+  This command should be run in the root directory of the repo.
   It will create or update the .gitmodules file and include
   `gclient-condition` values. Commits in gitlinks will also be updated.
   """