Don't rely on vi.mock internals in unit tests

Author: wojtekmaj

src/Calendar.spec.jsx

@@ -33,7 +33,7 @@ describe('Calendar', () => {
     render(<Calendar inputRef={inputRef} />);
 
     expect(inputRef).toHaveBeenCalled();
-    expect(inputRef.mock.calls[0][0]).toBeInstanceOf(HTMLElement);
+    expect(inputRef).toHaveBeenCalledWith(expect.any(HTMLElement));
   });
 
   it('renders Navigation by default', () => {