add omitempty to RegistrationDriver field (#343)

Signed-off-by: haoqing0110 <[email protected]>

operator/v1/types_klusterlet.go

@@ -180,9 +180,10 @@ type RegistrationConfiguration struct {
 
 type RegistrationDriver struct {
 	// Type of the authentication used by managedcluster to register as well as pull work from hub. Possible values are csr and awsirsa.
+	// +required
 	// +kubebuilder:default:=csr
 	// +kubebuilder:validation:Enum=csr;awsirsa
-	AuthType string `json:"authType"`
+	AuthType string `json:"authType,omitempty"`
 
 	// Contain the details required for registering with hub cluster (ie: an EKS cluster) using AWS IAM roles for service account.
 	// This is required only when the authType is awsirsa.