Describe the Bug

The types for return values from Kafka.structured(cloudEventInstance) seem to be incorrect. The returned object has the following structure if viewed using logs or a debugger:

{
  key: 'fubar',
  value: '{"id":"ef233aa0-00a0-4b5a-9886-f8ff7566ef50","time":"2022-04-14T20:26:32.291Z","type":"foo","source":"bar","specversion":"1.0","partitionkey":"fubar","data":{"hello":"world}}',
  headers: { 'content-type': 'application/cloudevents+json; charset=utf-8' },
  body: '{"id":"ef233aa0-00a0-4b5a-9886-f8ff7566ef50","time":"2022-04-14T20:26:32.291Z","type":"foo","source":"bar","specversion":"1.0","partitionkey":"fubar","data":{"hello":"world}}',
  timestamp: '1649967992291'
}

However, the types come from CE.Message<string>. This results in the following intellisense structure being suggested:

{
  body: unknown,
  headers: CE.Headers
}

It seems as though the headers key is correct, but the body is incorrect, and other keys are missing.

Steps to Reproduce

1. Create a CloudEvent, e.g new ce.CloudEvent({ type: 'foo', source: 'bar', data: { hello: 'world' }, partitionkey: 'foobar' }
2. Pass it to, e.g Kafka.structured(theEvent)
3. Attempt to access the timestamp, value, or key. These are not known properties on the return value.
4. Try to use the body and you find it is incorrectly typed as unknown

Expected Behavior

I would have expected the types to reflect the Object in the Describe the bug section, e.g:

{
  key: string|undefined
  value: string,
  headers: CE.Headers,
  body: string,
  timestamp: string
}

Is this an invalid assumption to make? Passing the result of Kafka.structured(cloudEventInstance) object to a Kafka client such as KafkaJS requires casting the object to access the necessary properties to satisfy the TS compiler. It seems like this casting should be unnecessary.

Additional context

I'm using version 6.0.1 of the cloudevents module. The image below might help provide some context.