add isRelevant check on flowStep predicate

Author: erik-krogh

javascript/ql/src/semmle/javascript/dataflow/Configuration.qll

@@ -1106,6 +1106,7 @@ private predicate flowStep(
     // Flow into higher-order call
     flowIntoHigherOrderCall(pred, succ, cfg, summary)
   ) and
+  isRelevant(succ, cfg) and
   not cfg.isBarrier(succ) and
   not isBarrierEdge(cfg, pred, succ) and
   not isLabeledBarrierEdge(cfg, pred, succ, summary.getEndLabel()) and