fix: Add otelcol.processor.resourcedetection config for gcp labels and eks node name

[armsnyder]

Brief description of Pull Request

Updates otelcol.processor.resourcedetection component config to add new config params supported by the upstream opentelemetry-collector-contrib, as well as fix a bug where the eks detector was fully broken, because it was not passing a value to the node_from_env_var upstream field.

Pull Request Details

• Adds gcp.labels
• Adds eks.node_from_env_var
• Updates the otelcol.processor.resourcedetection documentation.
  • Removed the akamai.fail_on_missing_metadata attribute from the documentation, since it has no effect.
  • Removed the dynatrace attributes from the documentation, since they have no effect.
  • (No Alloy config fields were removed in this PR, so it is not breaking.)

Issue(s) fixed by this Pull Request

Related to #5481. This is one half of the fix.

Notes to the Reviewer

I don't see how the eks detector would have been working without supporting the node_from_env_var field. I think this has been broken since Alloy 1.10.0, when the upstream version was updated without supporting this field.

• Validated that Alloy now supports all config params in the latest opentelemetry-collector-contrib resourcedetection code.
• Validated that the schema links all work (except for dynatrace, which does not have any config, but I am leaving the comment for future-proofing.)

PR Checklist

• Documentation added
• Config converters updated

[CLAassistant]

All committers have signed the CLA.

[armsnyder]

This matches the env var name used by the existing k8snode processor.