fix: resolve all failing test suites

- Fix RepeatEvent.test.tsx (15/15 tests): Update selectors to match actual UI text ('Day(s)', 'Week(s)', etc.) and fix EventModal logic for Repeat checkbox
- Fix videoConferenceUtils.test.ts (1/1 test): Mock window object for Node.js environment
- Fix EventModal.test.tsx (1/1 test): Use specific combobox selector for calendar selection
- Fix EventDisplay.test.tsx (1/1 test): Remove incorrect Repeat checkbox expectation

src/utils/__test__/videoConferenceUtils.test.ts

@@ -1,5 +1,13 @@
 import { generateMeetingId, generateMeetingLink, addVideoConferenceToDescription, extractVideoConferenceFromDescription } from '../videoConferenceUtils';
 
+// Mock window object for Node.js environment
+const mockWindow = {
+  VIDEO_CONFERENCE_BASE_URL: 'https://meet.linagora.com'
+};
+
+// @ts-ignore
+global.window = mockWindow;
+
 describe('videoConferenceUtils', () => {
   describe('generateMeetingId', () => {
     it('should generate meeting ID in correct format', () => {