[processor/resourcedetection] refactor eks detector to fetch attributes from k8s and AWS api

[dloucasfx]

Description

• refactored EKS detector to use the ec2 metadata provider when the metadata server is available . Metadata server will take priority over k8s/aws api as it's more robust
• added EKS metadata provider which uses the k8s and aws api to gather attributes . This is needed when IMDS is not accessible . (ex: EKS Auto Mode and/or pod not running in hostnetwork)
• use the new EKS metadata provider in EKS detector when IMDS server is NOT available.
• added extra resource attributes to the EKS detector (region, availability region, instanceid) . As those attributes will fail in the ec2 detector when IMDS is not accessible

As mentioned in my note in the linked issue, extra care is need to enable AWS Auth when IMDS is not accessible

While developing the above suggestion, I have noticed that AWS API client gets its auth credentials through the metadata server endpoint. In other words, we can no longer "transparently" use AWS API calls in EKS AUTO MODE (non hostnetwork pod) as this endpoint is not reachable.
This means that the user needs to explicitly define the AWS credentials. This can be done through different means, example, env variables or using POD Identity.
Pod Identity is the best choice as the agent identity is pre-installed in EKS Auto Mode and the user will only need to create the appropriate role and associate it with the pod SA.

Link to tracking issue

Fixes #39503

Testing

And once I get an OK from the community, I will update this PR with the test files (for the EKS metadata provider and the eks detector)

Documentation

Auto generated docs.
And once I get an OK from the community, I will add extra notes on how to enable auth and extra info

Note:

I can break the PR into EKS metada provider and EKS resource detection if needed.