bluetooth.conf: Add DBus.Properties interface
bluetooth.conf: Add DBus.Properties interface

GattManager1 communicates with external services using their properties.
This patch adds the org.freedesktop.DBus.Properties interface to the
list of allowed interfaces in the D-Bus configuration.

pkarasev3/bluez,pstglia/external-bluetooth-bluez,silent-snowman/bluez,silent-snowman/bluez,ComputeCycles/bluez,pkarasev3/bluez,silent-snowman/bluez,ComputeCycles/bluez,mapfau/bluez,pstglia/external-bluetooth-bluez,silent-snowman/bluez,pkarasev3/bluez,mapfau/bluez,pstglia/external-bluetooth-bluez,mapfau/bluez,pkarasev3/bluez,ComputeCycles/bluez,ComputeCycles/bluez,mapfau/bluez,pstglia/external-bluetooth-bluez