feat: Use vitest instead of jest, run all the specs anywhere in app/ folder in the CI (#9722)

Due to the pattern `**/specs/*.spec.js` defined in CircleCI, none of the
frontend spec in the folders such as
`specs/<domain-name>/getters.spec.js` were not executed in Circle CI.

This PR fixes the issue, along with the following changes: 
- Use vitest instead of jest
- Remove jest dependancies
- Update tests to work with vitest

---------

Co-authored-by: Muhsin Keloth <muhsinkeramam@gmail.com>

app/javascript/shared/helpers/specs/CustomErrors.spec.js

@@ -1,4 +1,4 @@
-const { DuplicateContactException } = require('../CustomErrors');
+import { DuplicateContactException } from '../CustomErrors';
 
 describe('DuplicateContactException', () => {
   it('returns correct exception', () => {

app/javascript/shared/helpers/specs/CustomEventHelper.spec.js

@@ -2,7 +2,7 @@ import { dispatchWindowEvent } from '../CustomEventHelper';
 
 describe('dispatchWindowEvent', () => {
   it('dispatches correct event', () => {
-    window.dispatchEvent = jest.fn();
+    window.dispatchEvent = vi.fn();
     dispatchWindowEvent({ eventName: 'chatwoot:ready' });
     expect(dispatchEvent).toHaveBeenCalled();
   });

app/javascript/shared/helpers/specs/mitt.spec.js

@@ -2,7 +2,7 @@ import { emitter } from '../mitt';
 
 describe('emitter', () => {
   it('should emit and listen to events correctly', () => {
-    const mockCallback = jest.fn();
+    const mockCallback = vi.fn();
 
     // Subscribe to an event
     emitter.on('event', mockCallback);