machine_webhooks: GCP now supports SEV on c3d machines

Extend gcpConfidentialComputeSupportedMachineSeries to also consider c3d
machines capable of running SEV confidential machines.

Author: bgartzi

pkg/webhooks/machine_webhook.go

@@ -225,7 +225,7 @@ const (
 
 // GCP Confidential VM supports Compute Engine machine types in the following series:
 // reference: https://cloud.google.com/compute/confidential-vm/docs/os-and-machine-type#machine-type
-var gcpConfidentialComputeSupportedMachineSeries = []string{"n2d", "c2d"}
+var gcpConfidentialComputeSupportedMachineSeries = []string{"n2d", "c2d", "c3d"}
 
 // defaultInstanceTypeForCloudProvider returns the default instance type for the given cloud provider and architecture.
 // If the cloud provider is not supported, an empty string is returned.

pkg/webhooks/machine_webhook_test.go

@@ -3825,7 +3825,7 @@ func TestValidateGCPProviderSpec(t *testing.T) {
 				p.MachineType = "e2-standard-4"
 			},
 			expectedOk:    false,
-			expectedError: "providerSpec.machineType: Invalid value: \"e2-standard-4\": ConfidentialCompute require machine type in the following series: n2d,c2d",
+			expectedError: "providerSpec.machineType: Invalid value: \"e2-standard-4\": ConfidentialCompute require machine type in the following series: n2d,c2d,c3d",
 		},
 		{
 			testCase: "with GPUs and Migrate onHostMaintenance",