minor refactoring

Signed-off-by: Sandesh Kumar <sandeshkr419@gmail.com>

Author: sandeshkr419

server/src/main/java/org/opensearch/search/aggregations/bucket/terms/TermsAggregator.java

@@ -291,10 +291,11 @@ private boolean subAggsNeedScore() {
 
     @Override
     protected boolean shouldDefer(Aggregator aggregator) {
-        // don't defer when StarTreeContext is set, don't defer when collectMode == SubAggCollectionMode.BREADTH_FIRST
-        // this boolean condition can be further simplified but affects readability.
-        return (context.getQueryShardContext().getStarTreeQueryContext() == null || collectMode != SubAggCollectionMode.BREADTH_FIRST)
-            && collectMode == SubAggCollectionMode.BREADTH_FIRST
-            && !aggsUsedForSorting.contains(aggregator);
+        if (context.getQueryShardContext().getStarTreeQueryContext() == null) {
+            return collectMode == SubAggCollectionMode.BREADTH_FIRST && !aggsUsedForSorting.contains(aggregator);
+        } else {
+            // when pre-computing using star-tree - return false (don't defer) for BREADTH_FIRST case
+            return collectMode != SubAggCollectionMode.BREADTH_FIRST;
+        }
     }
 }