Add template for ArcGIS Server on Windows

Add a template that provides GitHub Actions workflows for ArcGIS Server deployment & operations on Windows platform.

The template should use:
- Packer for AMI builds,
- Terraform for creating AWS resources,
- [PowerShell DSC](https://github.com/Esri/arcgis-powershell-dsc) for application configuration, and
- Ansible to install PowerShell DSC modules and run PowerShell remotely using [aws_ssm connection](https://docs.ansible.com/ansible/latest/collections/community/aws/aws_ssm_connection.html).