[EKS Fargate] [request]: Allow updating the EKS Fargate profile pod selectors

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>
> **Tell us about your request** Allow updating the EKS Fargate profile pod selectors.
>
> We should be able to edit the Fargate profile and modify namespace/labels.
>
> **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?** Currently EKS Fargate supports creating 5 namespaces and within those we can add 5 labels. but there is no way to edit a Fargate profile and add more namespaces/labels. For example if I created a fargate profile and at the time of creation added single namespace and 1 label in it, After that i can't add more namespaces and labels to it although it has a capacity of upto 5 namespaces and 5 labels in each namespace.
>
> **Are you currently working around this issue?** No
>
> **Additional context** N/A
>
> **Attachments** N/A

The issue names no repository files, tests, or entry points. Start by investigating how EKS Fargate profile selectors are created and whether namespace and label updates are supported; done means users can modify them within the stated limits.

Written by the indexing model from the issue text.