(triggers): custom resource driving a Trigger should be configurable to be placed in VPC

### Describe the feature

Expose the ability to set the VPC for the lambda driving the CustomResource inside a Trigger or TriggerFunction.

### Use Case

This lack was exposed inspecting our lambdas and finding which ones were not in a VPC. Anything that came from a Trigger (or TriggerFunction) had the underlying lambda outside the VPC. We seek to have all our lambdas inside our VPC.

### Proposed Solution

_No response_

### Other Information

Relevant code:
https://github.com/aws/aws-cdk/blob/v2.220.0/packages/aws-cdk-lib/triggers/lib/trigger.ts#L125-L134

Relevant issues:
https://github.com/aws/aws-cdk/issues/22456
https://github.com/aws/aws-cdk/issues/22473

### Acknowledgements

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

### AWS CDK Library version (aws-cdk-lib)

2.199.0

### AWS CDK CLI version

2.1017.0

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

Ubuntu 20.04.4 LTS

Read packages/aws-cdk-lib/triggers/lib/trigger.ts around lines 125-134, then trace how Trigger and TriggerFunction create the custom resource's Lambda. Review related issues #22456 and #22473 for context. Done means callers can configure the Lambda's VPC and the generated Lambda is placed in that VPC.

Written by the indexing model from the issue text.