refactor(client): move jest-dom into setup file

client/src/components/formHelpers/BlockSaveButton.test.js

@@ -1,6 +1,5 @@
 /* global expect */
 
-import '@testing-library/jest-dom/extend-expect';
 import React from 'react';
 import { render } from '@testing-library/react';
 

client/src/components/formHelpers/Form.test.js

@@ -1,5 +1,4 @@
 /* global jest, expect */
-import '@testing-library/jest-dom/extend-expect';
 
 import React from 'react';
 import { render, fireEvent } from '@testing-library/react';