Hello! when configuring a pub/sub push feed [1], could the push subscription be located in a different GCP project where Chronicle is running?

And, when configuring the push subscription and as it says in [2]:

"Select Enable authentication, and select a service account."

Which service account does Chronicle use? where can I find it?

(when using Google Cloud Storage it gives the possibility to configure a service account but not when using pub/sub, as shown in the following images: 

Thank you!

[1] https://cloud.google.com/chronicle/docs/administration/feed-management#pubsub-push-create

[2] https://cloud.google.com/chronicle/docs/administration/feed-management#specify-url-pubsub