[Story] Android: Add switch for dark / light / system mode to advanced settings

[VolkerJunginger]

Story

As a user that love to change the look of the app I want to be able to decide wether I want to use light or dark mode (or follow the system settings )so that I can sleep well at night knowing my app looks exactly like i want it to.

Ad an option to the advanced setting to switch between dark / light mode or to follow the system settings

This feature is already existing on iOS:

Dependencies

• TBD

Sign-offs

Android

• [ ] Design sign-off on completion
• [ ] QA sign-off on completion
• [ ] Product sign-off on completion

Scope

### Android
- [ ] Implemented
- [ ] https://github.com/vector-im/element-x-android/issues/1499

Out of scope

• TBD

[bmarty]

It has been done in https://github.com/vector-im/element-x-android/pull/1844, and is available for testing in nightly and in latest version from the store. @VolkerJunginger I let you close the issue once you have tested it?