修复h2数据库没有'Extra'字段导致异常问题

mybatis-plus-generator/src/main/java/com/baomidou/mybatisplus/generator/config/querys/H2Query.java

@@ -78,6 +78,6 @@ public class H2Query extends AbstractDbQuery {
 
     @Override
     public boolean isKeyIdentity(ResultSet results) throws SQLException {
-        return "auto_increment".equals(results.getString("Extra"));
+        return results.getString("SEQUENCE_NAME") != null;
     }
 }