Update to ACK runtime v0.20.1, code-generator v0.20.1 (#35)

### Update to ACK runtime `v0.20.1`, code-generator `v0.20.1`

----------

* ACK code-generator `v0.20.1` [release notes](https://github.com/aws-controllers-k8s/code-generator/releases/tag/v0.20.1)
* ACK runtime `v0.20.1` [release notes](https://github.com/aws-controllers-k8s/runtime/releases/tag/v0.20.1)

----------

NOTE:
This PR increments the release version of service controller from `v0.0.13` to `v0.0.14`

Once this PR is merged, release `v0.0.14` will be automatically created for `opensearchservice-controller`

**Please close this PR, if you do not want the new patch release for `opensearchservice-controller`**

----------

#### stdout for `make build-controller`:

```
building ack-generate ... ok.
==== building opensearchservice-controller ====
Copying common custom resource definitions into opensearchservice
Building Kubernetes API objects for opensearchservice
Generating deepcopy code for opensearchservice
Generating custom resource definitions for opensearchservice
Building service controller for opensearchservice
Generating RBAC manifests for opensearchservice
Running gofmt against generated code for opensearchservice
Updating additional GitHub repository maintenance files
==== building opensearchservice-controller release artifacts ====
Building release artifacts for opensearchservice-v0.0.14
Generating common custom resource definitions
Generating custom resource definitions for opensearchservice
Generating RBAC manifests for opensearchservice
```

----------

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

Author: ack-bot

apis/v1alpha1/ack-generate-metadata.yaml

@@ -1,11 +1,11 @@
 ack_generate_info:
-  build_date: "2022-03-25T18:19:20Z"
-  build_hash: c6b852a8017aa73cfc5a882b1ba60c88d820e967
+  build_date: "2022-09-12T19:43:28Z"
+  build_hash: 2944c8772f216656d84ee02d392eaca501274c1e
   go_version: go1.17.5
-  version: v0.18.1
-api_directory_checksum: b71af3be7579dea735994a82ef7595183473598b
+  version: v0.20.1
+api_directory_checksum: eef0a2635234f98159a89e22a8a3a2ee25e05f49
 api_version: v1alpha1
-aws_sdk_go_version: v1.42.0
+aws_sdk_go_version: v1.44.93
 generator_config_info:
   file_checksum: bd3133286f996b9a993aee42d06c278d88c24b2e
   original_file_name: generator.yaml