Set origin of metric (#1981)

### Description

The metric sets it for the origin label of `any` which is not as useful
as setting to the actual origin

rust/agents/relayer/src/msg/processor.rs

@@ -161,7 +161,7 @@ impl MessageProcessorMetrics {
         Self {
             max_last_known_message_nonce_gauge: metrics
                 .last_known_message_nonce()
-                .with_label_values(&["processor_loop", "any", "any"]),
+                .with_label_values(&["processor_loop", origin.name(), "any"]),
             last_known_message_nonce_gauges: gauges,
         }
     }