Is your feature request related to a problem? Please describe.
Currently, while using RemoteStorageHelper, you can only use keyStream – input stream for a JSON key as credentials for storage. I want to provide custom com.google.auth.Credentials because of how our internal systems manage access to Google Cloud.

Describe the solution you'd like
I want to add a method to RemoteStorageHelper that would enable providing the com.google.auth.Credentials.

  public static RemoteStorageHelper create(String projectId, Credentials credentials)