fix(modal): do not remove container from body if it has not been included yet

Author: assisrafael

src/dialog/ModalPortal.jsx

@@ -16,6 +16,10 @@ export function ModalPortal({ children, isOpen }) {
     }
 
     return () => {
+      if (!container) {
+        return;
+      }
+
       body.removeChild(container);
     };
   }, []);