remove unused code

Author: maochongxin

src/main/java/com/alipay/oceanbase/rpc/location/LocationUtil.java

@@ -43,7 +43,6 @@
 import java.sql.*;
 import java.text.MessageFormat;
 import java.util.*;
-import java.util.concurrent.atomic.AtomicBoolean;
 
 import static com.alipay.oceanbase.rpc.location.model.partition.ObPartitionKey.MAX_PARTITION_ELEMENT;
 import static com.alipay.oceanbase.rpc.location.model.partition.ObPartitionKey.MIN_PARTITION_ELEMENT;