message: Fix variable name on assert for SetClassByPosition
diff: @@ -867,8 +867,8 @@ ArgumentStack Creature::SetClassByPosition(ArgumentStack&& args)
  {
  const auto position = Services::Events::ExtractArgument<int32_t>(args);
  const auto classID = Services::Events::ExtractArgument<int32_t>(args);
  - assert(skill >= 0);
  - assert(skill <= 2);
  + assert(position >= 0);
  + assert(position <= 2);
  assert(classID >= 0);
  assert(classID <= 255);
  