HPCC-21541 Avoid accessing graphs stats from WUInfo service

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>

esp/services/ws_workunits/ws_workunitsHelpers.cpp

@@ -728,7 +728,7 @@ bool WsWuInfo::hasSubGraphTimings()
 {
     try
     {
-        WuScopeFilter filter("stype[subgraph],props[stat]");
+        WuScopeFilter filter("depth[3],stype[subgraph],stat[TimeElapsed],nested[0]");
         Owned<IConstWUScopeIterator> it = &cw->getScopeIterator(filter);
         ForEach(*it)
         {