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

__test__/features/Events/EventModal.test.tsx

@@ -184,7 +184,9 @@ describe("EventPopover", () => {
     const option = await screen.findByText("Calendar 2");
     fireEvent.click(option);
 
-    expect(screen.getAllByRole("combobox")[0]).toHaveTextContent("Calendar 2");
+    // Find the calendar combobox specifically by its aria-labelledby
+    const calendarSelect = screen.getByRole("combobox", { name: /Calendar/i });
+    expect(calendarSelect).toHaveTextContent("Calendar 2");
   });
   it("adds a attendee", async () => {
     jest.useFakeTimers();