Squashed commit of the following:
Squashed commit of the following:

commit 2a3e73af3a80a5603f9731604ab3c9a28e553c0b
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Wed May 27 13:42:16 2020 +0100

    Set send-to-device kafka topic

matrix-org/sytest,matrix-org/sytest