[EKS][AMI] [request]: Automatically update Managed node groups AMI with the security patches

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**Tell us about your request**
For EKS managed node group deployments, the node group should get updated automatically during the maintenance window (can be provided as an option) with the AMI with security patches release so that Admin doesn't have to keep track of the security patches and perform the manual update.

**Which service(s) is this request for?**
EKS Managed Node Group

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
If we are releasing an EKS based solution that will be deployed in the Customer AWS account. How will the Customer keep track of the security patches to be applied on the managed node group? For the other updates ( like the EKS version and another plugin release) a new CloudFormation template release can be provided to the customer to update the existing cluster, but for updating the managed node group with the security fixes customer has to perform it manually.

The issue does not identify repository files, tests, or implementation entry points. Start by checking whether this roadmap request has an implementation repository or an existing EKS managed node group update path; done would be a configurable maintenance-window option that applies security-patched AMIs without manual tracking.

Written by the indexing model from the issue text.