chore(deps): update dependency google-cloud-pubsub to v2.12.0 (#406)

Author: renovate-bot

asset/snippets/snippets/requirements.txt

@@ -1,5 +1,5 @@
 google-cloud-storage==2.2.1
 google-cloud-asset==3.8.1
 google-cloud-resource-manager==1.4.1
-google-cloud-pubsub==2.11.0
+google-cloud-pubsub==2.12.0
 google-cloud-bigquery==3.0.1