Add a setting to mongosync to change this default behavior:

"However, by default the API binds to localhost only and does not accept calls from other sources."
https://www.mongodb.com/docs/cluster-to-cluster-sync/current/reference/api/progress/#endpoint-protection

As requested here:
https://support.mongodb.com/case/01445699
and here:
https://www.mongodb.com/community/forums/t/mongosync-bind-setting/243454

To allow monitoring mongosync from elsewhere than localhost.