feat: add service_account to batch_prediction_job in aiplatform v1 batch_prediction_job.proto

PiperOrigin-RevId: 488416174

google/cloud/aiplatform/v1/batch_prediction_job.proto

@@ -204,6 +204,15 @@ message BatchPredictionJob {
   // must be provided.
   BatchDedicatedResources dedicated_resources = 7;
 
+  // The service account that the DeployedModel's container runs as. If not
+  // specified, a system generated one will be used, which
+  // has minimal permissions and the custom container, if used, may not have
+  // enough permission to access other GCP resources.
+  //
+  // Users deploying the Model must have the `iam.serviceAccounts.actAs`
+  // permission on this service account.
+  string service_account = 29;
+
   // Immutable. Parameters configuring the batch behavior. Currently only applicable when
   // [dedicated_resources][google.cloud.aiplatform.v1.BatchPredictionJob.dedicated_resources] are used (in other cases Vertex AI does
   // the tuning itself).