DEPS: Invoke play services hook with vpython

Otherwise it will inherit the empty python venv.

Bug: 869249
TBR: fbarchard
Change-Id: Ib77d116863f44f482b2cd7cbfaf71966ce2b7629
Reviewed-on: https://chromium-review.googlesource.com/1157535Reviewed-by: Ryan Tseng <hinoka@chromium.org>
Commit-Queue: Ryan Tseng <hinoka@chromium.org>

DEPS

@@ -801,7 +801,7 @@ hooks = [
     'pattern': '.',
     # When adding a new sdk extras package to download, add the package
     # directory and zip file to .gitignore in third_party/android_tools.
-    'action': ['python',
+    'action': ['vpython',
                'src/build/android/play_services/update.py',
                'download'
     ],