Fix memory leaks in mod storage (#7500)

src/script/lua_api/l_storage.cpp

@@ -58,6 +58,11 @@ StorageRef::StorageRef(ModMetadata *object):
 {
 }
 
+StorageRef::~StorageRef()
+{
+	delete m_object;
+}
+
 void StorageRef::create(lua_State *L, ModMetadata *object)
 {
 	StorageRef *o = new StorageRef(object);

src/script/lua_api/l_storage.h

@@ -50,7 +50,7 @@ private:
 
 public:
 	StorageRef(ModMetadata *object);
-	~StorageRef() = default;
+	~StorageRef();
 
 	static void Register(lua_State *L);
 	static void create(lua_State *L, ModMetadata *object);