Generate Transit Gateway using ACK runtime v0.15.1 (#17)

Issue #, if available:
aws-controllers-k8s/community#489

Description of changes:

process is broken up into commits between the generated and manual steps.

 - Generate Transit Gateway resource Create and Delete
 - Tests for Create and Delete (the sleeps on TGW create and delete are lengthy because the resource takes so long to be created and will error out if a delete is attempted while in a "pending" state)

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

Author: bwagner5

apis/v1alpha1/ack-generate-metadata.yaml

@@ -1,13 +1,13 @@
 ack_generate_info:
-  build_date: "2021-10-18T19:14:45Z"
-  build_hash: 21ee1672e2c1556fd5784a22bc48aa619975cc6f
-  go_version: go1.17
+  build_date: "2021-10-19T23:05:01Z"
+  build_hash: 7c6fc8daae2b1eddf00bfe9da797e6c5aab0ce7d
+  go_version: go1.16.6
   version: v0.15.1
-api_directory_checksum: 0f150b1176d3ba9246acb726466358f2877b24a8
+api_directory_checksum: ec534cc9172badabfaf6976400bb79a3d4e66c5d
 api_version: v1alpha1
 aws_sdk_go_version: v1.37.10
 generator_config_info:
-  file_checksum: af6d95e7cd2066fe11752abd324daf8e051be09f
+  file_checksum: c47b31195e00afb6637d63b44560fb2b82245978
   original_file_name: generator.yaml
 last_modification:
   reason: API generation

apis/v1alpha1/enums.go

@@ -7,6 +7,7 @@ ignore:
     - CreateSubnetInput.DryRun
     - CreateRouteTableInput.DryRun
     - CreateInternetGatewayInput.DryRun
+    - CreateTransitGatewayInput.DryRun
   resource_names:
     - AccountAttribute
     - CapacityReservation
@@ -55,7 +56,7 @@ ignore:
     - TransitGatewayRouteTable
     - TransitGatewayRoute
     - TransitGatewayVpcAttachment
-    - TransitGateway
+    #- TransitGateway
     - Volume
     - VpcEndpointConnectionNotification
     - VpcEndpointServiceConfiguration
@@ -66,6 +67,8 @@ ignore:
     - VpnConnectionRoute
     - VpnConnection
     - VpnGateway
+  operations:
+    - ModifyTransitGateway
 
 operations:
   CreateVpcEndpoint: