(neptune-alpha): Add latest engine versions and supported instance types

[triggan]

Describe the feature

Add Engine Versions 1.3.2.0, 1.3.2.1, 1.3.3.0, 1.2.1.1, and 1.2.1.2 (https://docs.aws.amazon.com/neptune/latest/userguide/engine-releases.html).

Add latest set of supported instances:

• db.r6i.x (large to 32xlarge)
• db.r5d.x (large to 24xlarge)
• db.x2g.x (large to 16xlarge)
• db.x2iedn.x (xlarge to 32xlarge) (https://aws.amazon.com/neptune/pricing/)

Use Case

Provide users the ability to configure latest engine versions for a cluster along with the full list of supported instance types when using the neptune L2 construct (alpha).

Proposed Solution

No response

Other Information

No response

Acknowledgements

• [X] I may be able to implement this feature request
• [ ] This feature might incur a breaking change

CDK version used

2.154.1

Environment details (OS name and version, etc.)

N/A