Walkthrough examples to deploy on Graviton instances

[suniltheta]

Describe the request
Now that arm64 architecture support for App Mesh (envoy) aws/aws-app-mesh-roadmap#215 is available update the walkthrough examples to provision Graviton ECS/EKS instances so that we can run Arm64 envoy image on them.

Platform
EKS, ECS, EC2, etc.

Expected behavior
All example walkthrough updated to be provisioned on ARM platform. Or atleast some examples created to guide through Arm Envoy image support.

EKS/K8s platform: App Mesh controller for k8s now support arm from release v1.4.2. Update (howto-k8s-*) specific examples as well.

https://gallery.ecr.aws/appmesh/aws-appmesh-envoy