Implement KRM alternative for compute-v1-instance snippets

[Doooritooos]

Snippet to enhance:

• https://github.com/GoogleCloudPlatform/deploymentmanager-samples/blob/master/google/resource-snippets/compute-v1/instance.yaml
• https://github.com/GoogleCloudPlatform/deploymentmanager-samples/blob/master/google/resource-snippets/compute-v1/instance_without_labels.yaml

More details: go/dm-snippets-alternatives Example: #593, #627