SIENTIAPDE-1174

pdate metrics tracking to include response time histogram

- Changed PREDICTION_RESPONSE_TIME_MONITOR from Gauge to Histogram for better response time analysis.
- Updated response time observation method in gates.py to utilize the new Histogram functionality.

laborious/activities/gates.py

@@ -340,4 +340,4 @@ class Gates(BaseActivity):
             pod_id=self.pod_id,
             model_name=metadata['model_name'],
             pipeline_name=metadata['workflow_name']
-        ).set(response_time)
+        ).observe(response_time)