feat(challenge20): setup test for challenge

apps/testing-modal/src/app/app.component.cy.ts

@@ -0,0 +1,19 @@
+import { AppComponent } from './app.component';
+
+describe(AppComponent.name, () => {
+  const setup = () => {
+    cy.mount(AppComponent);
+  };
+
+  test('error modal is displayed if you click on "Confirm" without inputing a name', () => {
+    setup();
+  });
+
+  test('error message is shown if you click "Cancel" in the confirmation modal after submitting a name', () => {
+    setup();
+  });
+
+  test('confirm message is shown if you click "Confirm" in the confirmation modal after submitting a name', () => {
+    setup();
+  });
+});