Summary:
No need to emit newConnection in Server::incomingConnection because QTcpServer will emit it after incomingConnection returns
QTcpServer also already has a list of pending connections so use that
Test Plan: Send a file from desktop to android and observe that newConnection is only called once
Reviewers: #kde_connect, albertvaka
Reviewed By: #kde_connect, albertvaka
Subscribers: kdeconnect
Tags: #kde_connect
Differential Revision: https://phabricator.kde.org/D17009