test(frontend):Updated cookie exist test

packages/code-du-travail-frontend/src/common/__tests__/CookieConsent.test.js

@@ -1,10 +1,16 @@
 import React from "react";
 import { render } from "@testing-library/react";
+import cookie from "js-cookie";
 import CookieConsent from "../CookieConsent";
 
 describe("<CookieConsent />", () => {
   it("should render", () => {
     const { container } = render(<CookieConsent />);
     expect(container).toMatchSnapshot();
   });
+  it("should not render if cookie exist", () => {
+    cookie.get = jest.fn().mockImplementation(() => true);
+    const { container } = render(<CookieConsent />);
+    expect(container).toMatchSnapshot();
+  });
 });

packages/code-du-travail-frontend/src/common/__tests__/__snapshots__/CookieConsent.test.js.snap

@@ -1,5 +1,7 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`<CookieConsent /> should not render if cookie exist 1`] = `<div />`;
+
 exports[`<CookieConsent /> should render 1`] = `
 .c6 {
   display: inline-block;