Which service account GCP_ENVIRONMENT refer to in apoc.load.csv?

Hi community

As you can read here

We can use apoc.load.csv with gs once all plugins are installed
It works well, but I have some user rights issues when using it because I don't know which service account I must update the rights. I'm using the GCP_ENVIRONMENT authentification type, so it says...

GCP_ENVIRONMENT: for passive authentication as a service account when Neo4j is running in the Google Cloud

As a service account, but which one, there is more than one service account in my google env

Thanks