feat: Exposing AutoscalingConfig in InstancePartition (#2449)

* feat: Exposing AutoscalingConfig in InstancePartition

PiperOrigin-RevId: 825184314

Source-Link: googleapis/googleapis@72e7439

Source-Link: googleapis/googleapis-gen@007caa0
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Author: gcf-owl-bot[bot]

protos/google/spanner/admin/instance/v1/spanner_instance_admin.proto

@@ -1755,6 +1755,13 @@ message InstancePartition {
     int32 processing_units = 6;
   }
 
+  // Optional. The autoscaling configuration. Autoscaling is enabled if this
+  // field is set. When autoscaling is enabled, fields in compute_capacity are
+  // treated as OUTPUT_ONLY fields and reflect the current compute capacity
+  // allocated to the instance partition.
+  AutoscalingConfig autoscaling_config = 13
+      [(google.api.field_behavior) = OPTIONAL];
+
   // Output only. The current instance partition state.
   State state = 7 [(google.api.field_behavior) = OUTPUT_ONLY];