Improve process handling

docker/Dockerfile

@@ -47,4 +47,4 @@ RUN chmod +x /opt/scrutiny/bin/scrutiny && \
     chmod -R ugo+rwx /opt/scrutiny/config
 
 
-CMD ["/init"]
+ENTRYPOINT ["/init"]

docker/entrypoint-collector.sh

@@ -25,4 +25,4 @@ fi
 
 # now that we have the env start cron in the foreground
 echo "starting cron"
-su -c "cron -f -L 15" root
+exec cron -f -L 15

rootfs/etc/services.d/collector-once/run

@@ -10,4 +10,4 @@ s6-svc -O /var/run/s6/services/collector-once
 until $(curl --output /dev/null --silent --head --fail http://localhost:8080/api/health); do echo "scrutiny api not ready" && sleep 5; done
 
 echo "starting scrutiny collector (run-once mode. subsequent calls will be triggered via cron service)"
-/opt/scrutiny/bin/scrutiny-collector-metrics run
+exec /opt/scrutiny/bin/scrutiny-collector-metrics run

rootfs/etc/services.d/cron/run

@@ -1,4 +1,4 @@
 #!/usr/bin/with-contenv bash
 
 echo "starting cron"
-cron -f -L 15
+exec cron -f -L 15

rootfs/etc/services.d/influxdb/run

@@ -14,4 +14,4 @@ EOF
 fi
 
 echo "starting influxdb"
-influxd run
+exec influxd run

rootfs/etc/services.d/scrutiny/run

@@ -4,4 +4,4 @@ echo "waiting for influxdb"
 until $(curl --output /dev/null --silent --head --fail http://localhost:8086/health); do echo "influxdb not ready" && sleep 5; done
 
 echo "starting scrutiny"
-scrutiny start
+exec scrutiny start