Set EventRef.ResultEventRef to optional

Signed-off-by: Dmitrii Tikhomirov <chani.liet@gmail.com>

Author: treblereel

model/event.go

@@ -96,7 +96,7 @@ type EventRef struct {
 	// +kubebuilder:validation:Required
 	TriggerEventRef string `json:"triggerEventRef" validate:"required"`
 	// Reference to the unique name of a 'consumed' event definition
-	// +kubebuilder:validation:Required
+	// +optional
 	ResultEventRef string `json:"resultEventRef" validate:"required"`
 	// Maximum amount of time (ISO 8601 format) to wait for the result event. If not defined it be set to the
 	// actionExecutionTimeout