sdk-dbus-tools-d-feet: Switch from folks-inspect to dbus-test-tool to generate dbus activity

The current sdk-dbus-tools-d-feet test doesn't work because folks-inspect has been removed from Apertis and cannot be used anymore to test d-feet. Instead, we can use the dbus test tool to generate traffic.

https://phabricator.apertis.org/T6024

Signed-off-by: Dylan Aïssi dylan.aissi@collabora.com