Disable systemd services while stopping them

This removes some `multi-target.wants` symlinks as well, etc.

But despite systemd saying:

> Removed symlink /etc/systemd/system/matrix-synapse.service.wants/matrix-synapse-worker@appservice:0.service

.. I still see such symlinks tehre for me for some reason, so keeping the
code (below) to find & delete them still seems like a good idea.

roles/matrix-base/templates/usr-local-bin/matrix-remove-all.j2

@@ -22,7 +22,7 @@ else
 	# '/etc/systemd/system/matrix-synapse.service.wants/matrix-synapse-worker@generic_worker:18111.service'
 	# and stop these instantiated services as well.
 	for s in $(find {{ matrix_systemd_path }}/ -xtype f -name "matrix-*" -printf "%f\n" | grep -v '@.service' | uniq); do
-		systemctl stop $s
+		systemctl disable --now $s
 	done
 
 	# Get rid of regular service files, as well as symlinks like