usage-stats-url has to be reachable

[ESCRI11]

Bug found when using shinyproxy 3.1.1

On my deployment I set the usage-stats-url to send data to my monitoring stack. The monitoring stack crashed for unrelated reasons, causing the URL to become unreachable. It seems that when this happens, shinyproxy stops working.

The weird thing is that I did not get any error on the service log of shinyproxy/seats started by shinyproxy. Making this quite a headache to diagnose when my deployment was just not responding at all. I would just expect everything to be nominal when the URL is unreachable.

If needed I can share further details on the exact settings of my deployment, should this issue not be reproducible.