Joy Haldar

Hello @talatuyarer, @ebyhr, @nastra, i would really appreciate it if you could please take a look if you have some time.

> @joyhaldar Thanks for working at this! I think service account impersonation is relevant also outside of the BigQueryMetastoreCatalog context - basically for every workload running on GCP, so I...

> Is the service account impersonation support for the catalog, fileio, or both? > > I see there's already a [GoogleAuthManager class](https://github.com/apache/iceberg/blob/main/gcp/src/main/java/org/apache/iceberg/gcp/auth/GoogleAuthManager.java) for handling auth and google credential. It uses...