Fix livewire return type to make sure it can return everything in the…

… data object (#836)

src/Support/Livewire/LivewireDataSynth.php

@@ -30,7 +30,7 @@ public static function match($target): bool
         return $target instanceof BaseData && $target instanceof TransformableData;
     }
 
-    public function get(&$target, $key): BaseData
+    public function get(&$target, $key): mixed
     {
         return $target->{$key};
     }