chore(deps): update dependency google-cloud-pubsub to v2.7.0 (#460)

Author: renovate-bot

packages/google-cloud-pubsub/samples/snippets/requirements.txt

@@ -1,2 +1,2 @@
-google-cloud-pubsub==2.6.1
+google-cloud-pubsub==2.7.0
 avro==1.10.2