fix(ui): import jest for react tests (#231)

Co-authored-by: Mihkel.Paloots <[email protected]>

libs/react-ui/src/lib/button/button.spec.tsx

@@ -1,6 +1,7 @@
 import React from 'react';
 import { render } from '@testing-library/react';
 import ButtonComponent from './button';
+import { expect, describe, it } from '@jest/globals';
 
 describe('ButtonComponent', () => {
   it('renders without crashing', () => {