Postgresql LCN : This ResultSet is closed

- [ ] I have searched the [issues](https://github.com/codingapi/tx-lcn/issues) of this repository and believe that this is not a duplicate.

### 1. Bug Description
调用http://localhost:12011/txlcn?value=the-value
在txlcn-demo-spring-service-b 中，出现
org.postgresql.util.PSQLException: This ResultSet is closed.

### 2. Environment:
- JDK version: 1.8
- OS: windows10
- TX-LCN version: 5.0.2
- Others:
database: postgresql
### 3. Exception Stacktrace

```
; uncategorized SQLException; SQL state [55000]; error code [0]; This ResultSet is closed.; nested exception is org.postgresql.util.PSQLException: This ResultSet is closed.] with root cause

org.postgresql.util.PSQLException: This ResultSet is closed.
at org.postgresql.jdbc.PgResultSet.checkClosed(PgResultSet.java:2741) ~[postgresql-42.2.5.jar:42.2.5]
at org.postgresql.jdbc.PgResultSet.getMetaData(PgResultSet.java:132) ~[postgresql-42.2.5.jar:42.2.5]
at com.zaxxer.hikari.pool.HikariProxyResultSet.getMetaData(HikariProxyResultSet.java) ~[HikariCP-3.2.0.jar:na]
```

### 4. Tour Idea
idea

Reproduce the request to http://localhost:12011/txlcn?value=the-value in txlcn-demo-spring-service-b using PostgreSQL, then trace the failure from PgResultSet.getMetaData through the Hikari proxy. No source file or test is named; done means the request no longer produces the PostgreSQL “This ResultSet is closed” exception.

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