1. add the action
2. add tests
3. describe to README

In CodeBuild CI, there was following error:
```
@aws-cdk/aws-iot-actions-alpha: - [yarn/nohoist-bundled-dependencies] Repository-level 'workspaces.nohoist' directive is missing: @aws-cdk/aws-iot-actions-alpha/case, @aws-cdk/aws-iot-actions-alpha/case/** (fixable)
@aws-cdk/aws-iot-actions-alpha: Error: Some package.json files had errors
@aws-cdk/aws-iot-actions-alpha:     at main (/codebuild/output/src514100616/src/github.com/aws/aws-cdk/tools/@aws-cdk/pkglint/bin/pkglint.js:30:15)
@aws-cdk/aws-iot-actions-alpha:     at Object.<anonymous> (/codebuild/output/src514100616/src/github.com/aws/aws-cdk/tools/@aws-cdk/pkglint/bin/pkglint.js:33:1)
@aws-cdk/aws-iot-actions-alpha:     at Module._compile (internal/modules/cjs/loader.js:999:30)
@aws-cdk/aws-iot-actions-alpha:     at Object.Module._extensions..js (internal/modules/cjs/loader.js:1027:10)
@aws-cdk/aws-iot-actions-alpha:     at Module.load (internal/modules/cjs/loader.js:863:32)
@aws-cdk/aws-iot-actions-alpha:     at Function.Module._load (internal/modules/cjs/loader.js:708:14)
@aws-cdk/aws-iot-actions-alpha:     at Module.require (internal/modules/cjs/loader.js:887:19)
@aws-cdk/aws-iot-actions-alpha:     at require (internal/modules/cjs/helpers.js:74:18)
@aws-cdk/aws-iot-actions-alpha:     at Object.<anonymous> (/codebuild/output/src514100616/src/github.com/aws/aws-cdk/tools/@aws-cdk/pkglint/bin/pkglint:2:1)
@aws-cdk/aws-iot-actions-alpha:     at Module._compile (internal/modules/cjs/loader.js:999:30)
```

…-cdk into aws-iot-actions-s3

as following:
error JSII9002: Unable to resolve type "@aws-cdk/aws-iot-actions.CommonActionProps". It may be @internal or not exported from the module's entry point (as configured in "package.json" as "main").