leave method
Have the current User remove themself from the contributors list.
Implementation
Future<void> leave() async {
if (_subreddit is! Subreddit) {
_subreddit = await _subreddit.populate();
}
final data = {
'id': (_subreddit as Subreddit).fullname,
};
await _subreddit.reddit
.post(apiPath['leavecontributor'], data, discardResponse: true);
}