updateSettings method Null safety

Implementation

@override
Future updateSettings(Settings settings) async {
  await _reddit.auth.refresh();
  http.Response ret = await http.patch(
      Uri.parse("https://oauth.reddit.com/api/v1/me/prefs"),
      body: json.encode({
        "video_autoplay": settings.autoplay,
        "over_18": settings.displayNsfw,
        "email_user_new_follower": settings.emailOnFollow,
        "email_username_mention": settings.emailOnMention,
        "email_post_reply": settings.emailOnReply,
        "email_upvote_post": settings.emailOnUpvote,
      }),
      headers: {
        "Authorization": "Bearer ${_reddit.auth.credentials.accessToken}",
        "User-Agent": "soreo"
      }
  );
  print(ret.statusCode);
}