Chores: remove unused helper method

Signed-off-by: Yuanchun Shen <yuanchu@amazon.com>

Author: yuancu

opensearch/src/main/java/org/opensearch/sql/opensearch/response/agg/BucketAggregationParser.java

@@ -122,16 +122,4 @@ public List<Map<String, Object>> parse(SearchHits hits) {
   protected Map<String, Object> extract(CompositeAggregation.Bucket bucket) {
     return bucket.getKey();
   }
-
-  /**
-   * Extracts key-value pairs from a range aggregation bucket without processing its
-   * sub-aggregations.
-   *
-   * @param bucket the range aggregation bucket to extract data from
-   * @param name the name to use as the key in the returned map
-   * @return a map containing the bucket's key mapped to the provided name
-   */
-  protected Map<String, Object> extract(Range.Bucket bucket, String name) {
-    return Map.of(name, bucket.getKey());
-  }
 }