Add urllib3 to docs dependencies

Jon Wayne Parrott · Jon Wayne Parrott · commit 6e7f0d98d5aa · 2016-10-18T13:32:26.000-07:00
diff --git a/packages/google-auth/docs/requirements-docs.txt b/packages/google-auth/docs/requirements-docs.txt
@@ -1 +1,2 @@
 sphinx-docstring-typing
+urllib3
