fix compile error

Sources/LiveObject.swift

@@ -107,10 +107,11 @@ public struct LiveObject<O: DynamicObject>: DynamicProperty {
                 let objectPublisher = objectPublisher?.asPublisher(in: dataStack)
             else {
 
-                self.objectPublisher = objectPublisher
+                self.objectPublisher = nil
                 self.item = nil
                 return
             }
+            
             self.objectPublisher = objectPublisher
             self.item = objectPublisher.snapshot