metrics: reduce cardinality on view names

rhodecode/lib/middleware/request_wrapper.py

@@ -64,7 +64,7 b' class RequestWrapperTween(object):'
 
             statsd = request.registry.statsd
             if statsd:
-                match_route = request.matched_route.name if request.matched_route else _path
+                match_route = request.matched_route.name if request.matched_route else "NOT_FOUND"
                 resp_code = getattr(response, 'status_code', 'UNDEFINED')
                 elapsed_time_ms = round(1000.0 * total)  # use ms only
                 statsd.timing(