Client metrics counter is not updated in the Web API end-point

[dmacvicar]

The client metrics are updated with a server interceptor.

	auth.UpdateMetrics = func(ctx context.Context) { Metrics.UpdateClientMetrics(ctx) }

Which calls the function in metrics.go to update the metrics based on the context peer data:

// UpdateClientMetrics ...
func (mc *MetricsCollection) UpdateClientMetrics(ctx context.Context) {
	p, ok := peer.FromContext(ctx)
	if ok && p != nil {
		ipAndPort := strings.Split(p.Addr.String(), ":")
		if len(ipAndPort) > 0 {
			mc.RPCsPerClientCounters.WithLabelValues(ipAndPort[0]).Inc()
			mc.LastMessageAtPerClientGauges.WithLabelValues(ipAndPort[0]).SetToCurrentTime()
		}
	}
}

We need to add a similar middleware to the Web API handler, so that these metrics get updated here as well.

At the moment it is not significant as people won't add much data from the console, but once we make the embedded REST API more visible, it will.