[aws_lambda_events] Add events for VPC Lattice

[andrewpatto]

A relatively new service I know - but one that matches well with existing API gateway support (it will not be much extra to add support with lambda-http - I will make a separate ticket for that).

First step I guess would be to add some of its event structure types.

https://docs.aws.amazon.com/vpc-lattice/latest/ug/lambda-functions.html