[Fargate/ECS/NLB] [request]: ECS Fargate NLB UDP container support in AWS CDK

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**Tell us about your request**
ECS Fargate NLB UDP container support in AWS CDK

**Which service(s) is this request for?**
ECS, Fargate, NLB

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
Got ECS Fargate service with NLB configured without problems with management console, but unable to do the same with AWS CDK stack. CDK seems to register container port of first container of the sevice to NLB and won't let define it as UDP, but only TCP is allowed? Not sure if this is right place to ask, bit is it so, that CDK is not yet supprting UDP containers with NLB and if so is that in roadmap?

**Are you currently working around this issue?**
No

Start by reproducing the ECS Fargate service and NLB configuration in an AWS CDK stack, comparing it with the management-console setup. Inspect how the CDK selects the first container port and permits TCP versus UDP. Done means CDK can represent the requested UDP container/NLB configuration and the behavior is covered by relevant tests.

Written by the indexing model from the issue text.