GlobalAccelerator: New API request GetEndpointGroupsForResource

[jukie]

This is a general API request and not specific to the Go SDK

Similar to GetWebACLForResource for WAF, I'd like the ability to find all EndpointGroup ARNs that a Resource ARN is associated with.

API Implementation in the sdk: https://github.com/aws/aws-sdk-go/blob/main/service/wafv2/api.go#L3688-L3702

Context: I'm seeking to add support for Global Accelerator to https://github.com/kubernetes-sigs/aws-load-balancer-controller but the lack of this API makes reconciling changes more difficult.