Add subnetIDs after custom describe to fix spec.subnetIDs: Required value (#111)

**Issue #, if available:** aws-controllers-k8s/community#1725

**Description of changes:**
- Adding the subnetIDs after the custom describe operation in order to populate the `spec.subnetIDs` field.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Author: mustafasencer

apis/v1alpha1/ack-generate-metadata.yaml

@@ -1,13 +1,13 @@
 ack_generate_info:
-  build_date: "2023-03-07T21:35:18Z"
+  build_date: "2023-03-10T17:52:20Z"
   build_hash: 910a8e0744a99c5c87d8c1615926985215a60d8c
   go_version: go1.19
   version: v0.24.3
 api_directory_checksum: 885f952f7ca2ce7a676b9bbf8eb262de71de6238
 api_version: v1alpha1
 aws_sdk_go_version: v1.44.93
 generator_config_info:
-  file_checksum: 2461349a2827ec98ae7440fbff3301c1effcfaf4
+  file_checksum: 8b1f9e0bb52e26722d71cbd1ee3d489a0e3970c6
   original_file_name: generator.yaml
 last_modification:
   reason: API generation

apis/v1alpha1/generator.yaml

@@ -18,6 +18,9 @@ resources:
         from:
           operation: DescribeEvents
           path: Events
+    hooks:
+      sdk_read_many_post_set_output:
+        template_path: hooks/cache_subnet_group/sdk_read_many_post_set_output.go.tpl
   ReplicationGroup:
     exceptions:
       terminal_codes:

generator.yaml

@@ -18,6 +18,9 @@ resources:
         from:
           operation: DescribeEvents
           path: Events
+    hooks:
+      sdk_read_many_post_set_output:
+        template_path: hooks/cache_subnet_group/sdk_read_many_post_set_output.go.tpl
   ReplicationGroup:
     exceptions:
       terminal_codes:

pkg/resource/cache_subnet_group/sdk.go

@@ -0,0 +1,6 @@
+
+        for _, subnetIdIter := range ko.Status.Subnets {
+                if subnetIdIter.SubnetIdentifier != nil {
+                        ko.Spec.SubnetIDs = append(ko.Spec.SubnetIDs, subnetIdIter.SubnetIdentifier)
+                }
+        }