this script is sourced by multiple scripts and we only need to do show
the station map URL once
also curl has long maximum timeouts which can block important services
from starting up if there is an issue with adsb.lol or the network / DNS
Move startup scripts to /etc/s6-overlay/startup.d
oneshot service named "startup" from underlying image executes
all files in /etc/s6-overlay/startup.d in alphabetical order
Remove various oneshot scripts from longrun service dependencies
Add "startup" oneshot service to longrun service dependencies
03-remove-mlathub-up deletes /run/mlathub_up when the container stops
As this file is created by the mlat-client service, remove it instead in
a finish script for mlat-client which is run when the mlat-client
service is stopped
02-remove-prometheus-data deletes /run/readsb-prometheus.prom when
the container stops
As this file is created by readsb, remove it instead in a finish script
for readsb which is run when the readsb service is stopped
