Use ESQL LIMIT in query (elastic#197017)

## Summary

At the moment the lack of `LIMIT` is causing our CI to log a lot of
these warnings as deprecation warnings.

This is not the final fix, but will reduce some of this logging in the
meantime.

x-pack/plugins/data_visualizer/public/application/index_data_visualizer/hooks/esql/use_esql_overall_stats_data.ts

@@ -91,7 +91,8 @@ const getESQLDocumentCountStats = async (
       ` | EVAL _timestamp_= TO_DOUBLE(DATE_TRUNC(${intervalMs} millisecond, ${getSafeESQLName(
         timeFieldName
       )}))
-    | stats rows = count(*) by _timestamp_`
+    | stats rows = count(*) by _timestamp_
+    | LIMIT 1000`
     );
 
     const request = {