feat: Extract instance type when provisioning VMs (#4839)

This should help us identify what instances our users consume.

provisioner/terraform/resources_test.go

@@ -287,6 +287,58 @@ func TestAppSlugValidation(t *testing.T) {
 	require.ErrorContains(t, err, "duplicate app slug")
 }
 
+func TestInstanceTypeAssociation(t *testing.T) {
+	t.Parallel()
+	type tc struct {
+		ResourceType    string
+		InstanceTypeKey string
+	}
+	for _, tc := range []tc{{
+		ResourceType:    "google_compute_instance",
+		InstanceTypeKey: "machine_type",
+	}, {
+		ResourceType:    "aws_instance",
+		InstanceTypeKey: "instance_type",
+	}, {
+		ResourceType:    "aws_spot_instance_request",
+		InstanceTypeKey: "instance_type",
+	}, {
+		ResourceType:    "azurerm_linux_virtual_machine",
+		InstanceTypeKey: "size",
+	}, {
+		ResourceType:    "azurerm_windows_virtual_machine",
+		InstanceTypeKey: "size",
+	}} {
+		tc := tc
+		t.Run(tc.ResourceType, func(t *testing.T) {
+			t.Parallel()
+			instanceType, err := cryptorand.String(12)
+			require.NoError(t, err)
+			resources, err := terraform.ConvertResources(&tfjson.StateModule{
+				Resources: []*tfjson.StateResource{{
+					Address: tc.ResourceType + ".dev",
+					Type:    tc.ResourceType,
+					Name:    "dev",
+					Mode:    tfjson.ManagedResourceMode,
+					AttributeValues: map[string]interface{}{
+						tc.InstanceTypeKey: instanceType,
+					},
+				}},
+				// This is manually created to join the edges.
+			}, `digraph {
+	compound = "true"
+	newrank = "true"
+	subgraph "root" {
+		"[root] `+tc.ResourceType+`.dev" [label = "`+tc.ResourceType+`.dev", shape = "box"]
+	}
+}`)
+			require.NoError(t, err)
+			require.Len(t, resources, 1)
+			require.Equal(t, resources[0].GetInstanceType(), instanceType)
+		})
+	}
+}
+
 func TestInstanceIDAssociation(t *testing.T) {
 	t.Parallel()
 	type tc struct {