[EKS][Fargate] [request]: Allow enabling sysctl flags for the Fargate kubelet

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**Tell us about your request**
Allow setting unsafe sysctl flags in the Fargate kubelet. This would allow updating the sysctl flags in the pod securityContext.

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

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
In order to set custom values for unsafe sysctl, we have to whitelist the unsafe sysctl at the kubelet level before it can be added to the pod securityContext and allowed in the pod security policy as per the kubernetes documentation [1]. By allowing this, it would enable us to customize the sysctl such as net.ipv4.tcp_timestamps,etc.

**Are you currently working around this issue?**
No workaround as of now.

**Reference Link**
[1] https://v1-16.docs.kubernetes.io/docs/tasks/administer-cluster/sysctl-cluster/#enabling-unsafe-sysctls

The request concerns the EKS Fargate kubelet and pod securityContext, with the Kubernetes unsafe-sysctl documentation as its only reference. Start by checking whether this public roadmap repository identifies an implementation entry point or test; done would require confirmed support for configuring the requested unsafe sysctls in Fargate.

Written by the indexing model from the issue text.