Update instance_setup.ps1
Update instance_setup.ps1

Fix Activation Status parsing.
GoogleCloudPlatform/compute-image-windows,Derekolds/compute-image-windows,illfelder/compute-image-windows,adjackura/compute-image-windows,ning-yang/compute-image-windows,ning-yang/compute-image-windows,adjackura/compute-image-windows,illfelder/compute-image-windows,GoogleCloudPlatform/compute-image-windows