Backend fails if `etcd` is down

If etcd is not reachable, the backend fails due to it getting stuck trying to audit the IP (since it's a request preprocess action),

The problem is here. This catches the request a preprocess it before continuing with our normal workflow. Since etcd is down, the request to audit fails https://gitlab.cern.ch/push-notifications/backend/-/blob/master/src/log/auditing.ts#L35, having as a result the backend down

https://cern.service-now.com/service-portal?id=outage&n=OTG0076071