Update to ACK runtime v0.56.0, code-generator v0.56.0 (#59)

### Update to ACK runtime `v0.56.0`, code-generator `v0.56.0`

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* ACK code-generator `v0.56.0` [release notes](https://github.com/aws-controllers-k8s/code-generator/releases/tag/v0.56.0)
* ACK runtime `v0.56.0` [release notes](https://github.com/aws-controllers-k8s/runtime/releases/tag/v0.56.0)

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NOTE:
This PR increments the release version of service controller from `v1.3.1` to `v1.4.0`

Once this PR is merged, release `v1.4.0` will be automatically created for `cloudwatch-controller`

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

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

```
building ack-generate ... ok.
==== building cloudwatch-controller ====
Copying common custom resource definitions into cloudwatch
Building Kubernetes API objects for cloudwatch
Generating deepcopy code for cloudwatch
Generating custom resource definitions for cloudwatch
Building service controller for cloudwatch
Running GO mod tidy
Generating RBAC manifests for cloudwatch
Running gofmt against generated code for cloudwatch
Updating additional GitHub repository maintenance files
==== building cloudwatch-controller release artifacts ====
Building release artifacts for cloudwatch-v1.4.0
Generating common custom resource definitions
Generating custom resource definitions for cloudwatch
Generating RBAC manifests for cloudwatch
```

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

Author: ack-bot

.github/workflows/postsubmit.yaml

@@ -0,0 +1,10 @@
+name: Hydrate Go Proxy
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  call-hydrate-go-proxy:
+    uses: aws-controllers-k8s/.github/.github/workflows/reusable-postsubmit.yaml@main