appengine: fix permadiff and cleanup

Author: KannetiDivya4a7

mmv1/products/appengine/StandardAppVersion.yaml

@@ -374,6 +374,7 @@ properties:
       - manual_scaling
     # This flattener is entirely handwritten and must be updated with **any** new field or subfield
     custom_flatten: templates/terraform/custom_flatten/appengine_standardappversion_automatic_scaling_handlenil.go.tmpl
+    default_from_api: true
     properties:
       - name: maxConcurrentRequests
         type: Integer

mmv1/templates/terraform/samples/services/appengine/app_engine_standard_app_version.tf.tmpl

@@ -72,18 +72,8 @@ resource "google_app_engine_standard_app_version" "myapp_v2" {
     port = "8080"
   }
 
-automatic_scaling {
-    max_concurrent_requests = 10
-    min_idle_instances = 1
-    max_idle_instances = 3
-    min_pending_latency = "1s"
-    max_pending_latency = "5s"
-    standard_scheduler_settings {
-      target_cpu_utilization = 0.5
-      target_throughput_utilization = 0.75
-      min_instances = 2
-      max_instances = 10
-    }
+  basic_scaling {
+    max_instances = 5
   }
 
   noop_on_destroy = true

mmv1/templates/terraform/samples/services/iap/iap_app_engine_service.tf.tmpl

@@ -40,10 +40,6 @@ resource "google_app_engine_standard_app_version" "version" {
   runtime         = "nodejs22"
   noop_on_destroy = true
 
-  // TODO: Removed basic scaling once automatic_scaling refresh behavior is fixed.
-  basic_scaling { 
-    max_instances = 5 
-  }
   entrypoint {
     shell = "node ./app.js"
   }