feat(stepfunctions-tasks): add httpinvoke step functions task (#28673)

This adds an `HttpInvoke` Step Functions task construct, which allows calling public APIs as described [here](https://docs.aws.amazon.com/step-functions/latest/dg/connect-third-party-apis.html).

- Accepts an Event Bridge API Destination `IConnection`, setting required permissions to use its credentials.
- Grants permission to invoke the root path for the endpoint (`apiRoot` prop). This allows passing the relative endpoint path at execution time (`apiEndpoint` prop).
- Defines an enum for the allowed options for the URL encoding style of arrays, used when encoding the request body.

Closes #28278

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