Resolve minbound maxbound NullPointerException (#64091)

Resolved nullPointerException in minbound and maxbound methods.

Fixes #62934

server/src/main/java/org/elasticsearch/search/aggregations/bucket/histogram/HistogramAggregationBuilder.java

@@ -194,12 +194,12 @@ public class HistogramAggregationBuilder extends ValuesSourceAggregationBuilder<
 
     /** Get the current minimum bound that is set on this builder. */
     public double minBound() {
-        return extendedBounds.getMin();
+        return DoubleBounds.getEffectiveMin(extendedBounds);
     }
 
     /** Get the current maximum bound that is set on this builder. */
     public double maxBound() {
-        return extendedBounds.getMax();
+        return DoubleBounds.getEffectiveMax(extendedBounds);
     }
 
     protected DoubleBounds extendedBounds() {