lwc-events: update log level (#1741)

Use info level for exceeding max group by size.

atlas-lwc-events/src/main/scala/com/netflix/atlas/lwc/events/DatapointConverter.scala

@@ -383,7 +383,7 @@ private[events] object DatapointConverter {
       }
       if (groups.size() >= MaxGroupBySize) {
         maxGroupsExceeded = true
-        logger.debug(s"max groups exceeded for expression: ${params.rawExpr}")
+        logger.info(s"max groups exceeded for expression: ${params.rawExpr}")
       }
     }