feat: Add IIFE

cypress/integration/other/iife.spec.js

@@ -0,0 +1,11 @@
+describe('IIFE', () => {
+  beforeEach(() => {
+    cy.visit('http://localhost:9000/iife.html');
+  });
+
+  it('should render when using mermaid.min.js', () => {
+    cy.window().should('have.property', 'rendered', true);
+    cy.get('svg').should('be.visible');
+    cy.get('#d2').should('have.text', 'Hello');
+  });
+});