Fix missing import java.util.Calendar in JDBCScanner

The Calendar class was used without being imported after backport #71046.

Author: luohaha

java-extensions/jdbc-bridge/src/main/java/com/starrocks/jdbcbridge/JDBCScanner.java

@@ -43,6 +43,7 @@
 import java.time.temporal.ChronoField;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Calendar;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;