fix(components): include mode classes on components for use in shadow (#17838)

- removes mode-less component classes from the internal CSS, use element instead
- adds mode specific classes `md` or `ios` for styling inside of shadow components
- adds e2e test that verifies mode classes exist on all ionic components, plus checks for specific classes that the components need for internal styling

fixes #17608

core/src/components/datetime/datetime-util.spec.ts

@@ -2,7 +2,7 @@ import { convertDataToISO, parseDate } from './datetime-util';
 
 describe('datetime-util', () => {
   describe('convertDataToISO', () => {
-    it('prints an emptry string for an empty datetime', () => {
+    it('prints an empty string for an empty datetime', () => {
       expect(convertDataToISO({})).toEqual('');
     });