anchor.diff:  	attributes := map[string]string{
   		"boot_disk.#":                       "1",
   		"disk.#":                            "1",
  -		"disk.0.image":                      "projects/debian-cloud/global/images/family/debian-9",
  +		"disk.0.image":                      "projects/debian-cloud/global/images/family/debian-11",
   		"disk.0.disk_encryption_key_raw":    "SGVsbG8gZnJvbSBHb29nbGUgQ2xvdWQgUGxhdGZvcm0=",
   		"disk.0.disk_encryption_key_sha256": "esTuF7d4eatX4cnc4JsiEiaI+Rff78JgPhA/v1zxX9E=",
   		"zone":                              zone,
  
positive.code: 	attributes := map[string]string{
  		"boot_disk.#":        "1",
  		"disk.#":             "2",
  		"disk.0.image":       "projects/debian-cloud/global/images/debian-9-stretch-v20180814",
  		"disk.0.auto_delete": "true",
  		"disk.1.image":       "global/images/family/debian-9",
  		"disk.1.auto_delete": "true",
  		"zone":               zone,
  	}
  
negative.code: 	diskName := fmt.Sprintf("instance-test-%s", randString(t, 10))
  	disk := &compute.Disk{
  		Name:        diskName,
  		SourceImage: "projects/debian-cloud/global/images/family/debian-11",
  		Zone:        zone,
  	}
  	op, err := config.NewComputeClient(config.userAgent).Disks.Insert(config.Project, zone, disk).Do()
  