[EKS] [fargate] [request]: Support graviton architecture for fargate nodes spawned by EKS

Currently, there seems to be no way to choose the architecture for fargate nodes spawned by EKS clusters.

This could be configurable in the fargate profile, or even better, transparently by setting the kubernetes.io/arch=arm64 nodeselector in kubernetes deployments

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**Tell us about your request**
What do you want us to build?

**Which service(s) is this request for?**
This could be Fargate, ECS, EKS, ECR

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
What outcome are you trying to achieve, ultimately, and why is it hard/impossible to do right now? What is the impact of not having this problem solved? The more details you can provide, the better we'll be able to understand and solve the problem.

**Are you currently working around this issue?**
How are you currently solving this problem?

**Additional context**
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No repository files, tests, or implementation entry points are named. Start by clarifying whether architecture should be selected in the EKS Fargate profile or inferred from Kubernetes deployments, then verify the supported EKS and Fargate behavior; done means a decided and implementable approach for Graviton nodes.

Written by the indexing model from the issue text.