The agent in bluez test has the possibility to accept everything.
It saves the tester from typing yes to continue the test everytime a
bluetooth event occurs. Thus reducing error and test duration.
This feature is already in use in bluez-hfp test.

Reviewed-by: Philip Withnall <philip.withnall@collabora.co.uk>
Signed-off-by: Frédéric Dalleau <frederic.dalleau@collabora.com>
Differential Revision: https://phabricator.apertis.org/D4907