[EKS] Update the key beta.kubernetes.io/os in addon manifest to kubernetes.io/os

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

Warning is reported when scaling coredns due to the deprecated key used in the addon manifest.

> Warning: spec.template.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms[0].matchExpressions[0].key: beta.kubernetes.io/os is deprecated since v1.14; use "kubernetes.io/os" instead
> Warning: spec.template.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms[0].matchExpressions[1].key: beta.kubernetes.io/arch is deprecated since v1.14; use "kubernetes.io/arch" instead

**Which service(s) is this request for?**

EKS

**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.

The key has enter deprecation since v1.14. For EKS managed addon this key needs to be changed within EKS.

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

NA

**Additional context**
Anything else we should know?

NA

**Attachments**
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Start by determining whether the EKS managed addon manifest is maintained in this repository or by an external EKS service; the issue provides no file or test entry point. Inspect the addon manifest location if available and verify that the deprecated beta.kubernetes.io/os and beta.kubernetes.io/arch keys are replaced with their current Kubernetes equivalents and no deprecation warning remains.

Written by the indexing model from the issue text.