message: fix: use full jid only for private chats
  fix
diff: @@ -32,8 +32,10 @@ export default class extends AbstractHandler {
  return this.PRESERVE_HANDLER;
  }
  + if (!peerContact.isGroupChat()) {
  // If we now the full jid, we use it
  peerContact.setResource(peerJid.resource);
  + }
  let message = new Message({
  uid: messageElement.getStanzaId(),
  