Contains information needed for generating an OpenID Connect token
<https://developers.google.com/identity/protocols/OpenIDConnect>__.
.. attribute:: service_account_email
\ Service account email
<https://cloud.google.com/iam/docs/service-accounts>__ to be
used for generating the OIDC token. The caller (for
CreateSubscription, UpdateSubscription, and ModifyPushConfig
RPCs) must have the iam.serviceAccounts.actAs permission for
the service account.