Let pipewire-pulse services conflict with their pulseaudio counterparts

You can only run either pulseaudio *or* the pipewire-pulse daemon at one
time. So make the pipewire-pulse units conflict with their pulseaudio
counterparts to avoid both running at the same time

src/daemon/systemd/user/pipewire-pulse.service.in

@@ -17,6 +17,7 @@ Requires=pipewire-pulse.socket
 ConditionUser=!root
 Wants=pipewire.service
 After=pipewire.service
+Conflicts=pulseaudio.service
 
 [Service]
 LockPersonality=yes

src/daemon/systemd/user/pipewire-pulse.socket

@@ -1,6 +1,7 @@
 [Unit]
 Description=PipeWire PulseAudio
 ConditionUser=!root
+Conflicts=pulseaudio.socket
 
 [Socket]
 Priority=6