launcher/start-service: use job-mode 'replace' also for transient units
launcher/start-service: use job-mode 'replace' also for transient units

This is a follow-up to 5d90e2d571b40ad6a8e9894f3bb38fe22d50fd06.

Signed-off-by: Tom Gundersen <7c8224529a7c718e876cb2496c973509fde1e50e@jklm.no>

bus1/dbus-broker