Supports use wildcards on "Allowed hosts" configure option

[czd890]

[a-abella]

I would like this also. I am using infinity to unify/flatten active alerts from many dozens of alertmanagers and grafana-built-in alertmanagers so all alerts can be visualized in one place. For us that means adding https://*-alertmanager.company.tld x20, and https://*-grafana.company.tld x20.

Wildcard would not only be nicer ux but would allow us to expand without forgetting to update the allowed hosts list.