aws-events: Enable schema discovery for Event Bus

### Describe the feature

The current EventBus construct doesn't allow enabling schema discovery.

### Use Case

Need to enable schema discovery for an event bus without using L1 constructs.

### Proposed Solution

This behaviour is supported in Cloudformation through [`AWS::EventSchemas::Discoverer`](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-eventschemas-discoverer.html).

This should be easily implemented on the EventBus.

e.g

```typescript
const eventBus = new EventBus(this, 'poll-events', {
schemaDiscovery: true
});
```

or to enable tagging we can do:

```typescript
const eventBus = new EventBus(this, 'poll-events')

const discoverer = eventBus.addDiscoverer()

cdk.Tags.of(discoverer).add('my-tag', 'yup')
```

### Other Information

_No response_

### Acknowledgements

- [X] I may be able to implement this feature request

### CDK version used

2.88.0

### Environment details (OS name and version, etc.)

Mac OS 13.4.1

Start from the EventBus construct entry point and read the linked AWS::EventSchemas::Discoverer resource documentation. Confirm how the requested schemaDiscovery option or addDiscoverer entry point should map to that resource; done means an EventBus can enable schema discovery without an L1 construct.

Written by the indexing model from the issue text.