AndroidPackageCreationStep: Ensure right thread for handleOutput()

The ::run method is run in a separate thread, yet the owner of the
buildstep is the gui thread. As such we need to use a DirectConnection
to ensure that the slot is called in the right thread.

Task-number: QTCREATORBUG-9660
Change-Id: Ia206f3256a23f70f50d31c739359ff24b952fe46
Reviewed-by: Paul Olav Tvete <paul.tvete@digia.com>
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>