Limit the worker to a single queue

config/root/etc/s6-overlay/s6-rc.d/tubesync-network-worker/run

@@ -1,4 +1,5 @@
 #!/command/with-contenv bash
 
 exec nice -n "${TUBESYNC_NICE:-1}" s6-setuidgid app \
-    /usr/bin/python3 /app/manage.py process_tasks
+    /usr/bin/python3 /app/manage.py process_tasks \
+    --queue network