Fixed an issue with the `GET /monitor` HTTP API where returned data could return values greater than reality depending on the requested time window.  For data points within 1 hour window, this distortion is merely visual in the dashboard.  For data points older than 1 hour, data is permanently distorted.

The impacted gauges are:

- `disconnected_durable_sessions`
- `subscriptions_durable`
- `subscriptions`
- `topics`
- `connections`
- `live_connections`