Use IMDSv1 to get hostname in AWS

Developer story

Leverage the IMDSv1 endpoint to fetch the instance hostname in AWS to avoid the dependency on the  AWS Tools for PowerShell library (https://github.com/aws/aws-tools-for-powershell) library that may not be available, especially in the BYOH use case.

Engineering Details

This approach was introduced in a previous PR (https://github.com/openshift/windows-machine-config-operator/pull/1284) for GCP.  

Use the Instance Metadata Service Version 1 (IMDSv1) to fetch the hostname in AWS. IMDSv1 will continue to be supported indefinitely as per AWS docs., hence is it safe to use it.

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instancedata-data-retrieval.html

Acceptance Criteria

• IMDSv1 is used to retrieve the hostname in AWS