feat(ec2): ebs optimized instance (#29962)

### Issue # (if applicable)

None

### Reason for this change

Cloudformation has `ebsOptimized` property for enabling EBS optimized instance.
This property is not configurable from L2.

### Description of changes

Add `ebsOptimized` property to `InstanceProps`.

### Description of how you validated changes

I've added both unit and integ tests.

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

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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: badmintoncryer