code: private boolean unregisterHelper(Supplier<Optional<AddOnModel>> suppAdd, Supplier<Optional<AddOnInformation>> suppAddInf) {
          boolean success1 = false;
          Optional<AddOnModel> addOnModel = suppAdd.get();
          if (addOnModel.isPresent()) {
              success1 = addOns.remove(addOnModel.get());
          }
  
          boolean success2 = false;
          Optional<AddOnInformation> addOnInformation = suppAddInf.get();
          if (addOnInformation.isPresent()) {
              success2 = addOnInformations.remove(addOnInformation.get());
          }
  
          return success1 && success2;
      }
docs: Helper to unregister an addOn.
  
  @param suppAdd The first get function to find the right addon.
  @param suppAddInf The second get function to find the right addonInformation.
  @return True if the operation was successful, otherwise false.