code: public FacetBuilder setItemsList(Map<String, String> items) {
          ArrayList<FacetWidgetItem> facetWidgetItems = new ArrayList<FacetWidgetItem>();
  
          for (String key : items.keySet()){
              String label = items.get(key);
              FacetWidgetItem facetWidgetItem = new FacetWidgetItem(key, label);
              facetWidgetItems.add(facetWidgetItem);
          }
          this.listItems = facetWidgetItems;
          return this;
      }
docs: Takes a map of value to labels and the unique name of the list
  @param items map of value to labels
  @return a Builder instance to allow chaining