Fix compile issue with QUERY_BITS

Copy this value from Lucene102BinaryQuantizedVectorsFormat where it became package private

Author: mayya-sharipova

server/src/main/java/org/elasticsearch/index/codec/vectors/diskbbq/ES920DiskBBQVectorsReader.java

@@ -27,7 +27,6 @@
 import java.io.IOException;
 import java.util.Map;
 
-import static org.apache.lucene.codecs.lucene102.Lucene102BinaryQuantizedVectorsFormat.QUERY_BITS;
 import static org.apache.lucene.index.VectorSimilarityFunction.COSINE;
 import static org.elasticsearch.index.codec.vectors.BQVectorUtils.discretize;
 import static org.elasticsearch.index.codec.vectors.OptimizedScalarQuantizer.DEFAULT_LAMBDA;
@@ -40,6 +39,9 @@
  */
 public class ES920DiskBBQVectorsReader extends IVFVectorsReader {
 
+    // QUERY_BITS value copied from Lucene102BinaryQuantizedVectorsFormat where it became package private
+    private static final byte QUERY_BITS = 4;
+
     ES920DiskBBQVectorsReader(SegmentReadState state, GenericFlatVectorReaders.LoadFlatVectorsReader getFormatReader) throws IOException {
         super(state, getFormatReader);
     }