According to RFC 6347 a DTLS server also must retransmit buffered message(s)
if timeouts happen during the handshake phase (so it's not a client only as
I initially understood it).
Conveniently so an auto-test is already in place and needs just a tiny
adjustment - handshakeWithRetransmission covers both sides.
Change-Id: If914ec3052e28ef5bf12a40e5eede45bbc53e8e0
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
5bd9f98342