The set of Google credentials registered with the Jenkins Credential Manager for authenticating with your project. This can be configured under "Manage Jenkins" -> "Manage Credentials".

NOTE: only suitable credentials will be listed. If nothing is showing up, please verify that your "Google Limited Service Account" has all the necessary scopes for this plugin (recommended). If you intend to use a "Google Service Account" directly, ensure you have checked the "Allow Unlimited Service Account Usage" check-box under advanced (not recommended).