Describe the feature

Postgres 16.4 was released to RDS a few days ago and should be supported by CDK.

Use Case

I would like to use 16.4 without constructing version manually.

Proposed Solution

No response

Other Information

No response

Acknowledgements

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

CDK version used

2.151.0

Environment details (OS name and version, etc.)

N/A