feat: implement addOrUpdateListItem method

tests/ListItemResponse.spec.ts

@@ -0,0 +1,19 @@
+import { ListItemResponse } from '../src/models/ListItemResponse';
+import { expect } from 'chai';
+
+describe('ListItemResponse', function () {
+  it('should be defined', function () {
+    expect(ListItemResponse).to.not.be.undefined;
+  });
+
+  it('should have a constructor with 1 parameter', function () {
+    expect(ListItemResponse).to.have.property('constructor');
+    expect(ListItemResponse.constructor).to.have.lengthOf(1);
+  });
+
+  it('should have a constructor that takes an id and sets the id property', function () {
+    const id = 1;
+    const listItemResponse = new ListItemResponse(id);
+    expect(listItemResponse).to.have.property('id', id);
+  });
+});