crosspost method
Crosspost a message to all channels following the channel it was sent in.
Implementation
Future<Message> crosspost(Snowflake id) async {
final route = HttpRoute()
..channels(id: channelId.toString())
..messages(id: id.toString())
..crosspost();
final request = BasicRequest(route, method: 'POST');
final response = await client.httpHandler.executeSafe(request);
final message = parse(response.jsonBody as Map<String, Object?>);
client.updateCacheWith(message);
return message;
}