SeataTransactionHolder.get(),Why not determine whether it is null, or if I want to rule null, how to do it?

[JsonLYH]

[linghengqian]

• Both the module and document issues have been fixed by Fixes the problem that the Seata integration module cannot correctly determine the status of distributed transactions in multi-microservice scenarios #32095. Feel free to check out https://shardingsphere.apache.org/document/current/cn/user-manual/shardingsphere-jdbc/special-api/transaction/seata/ in the master branch.
• If you do not introduce org.apache.shardingsphere:shardingsphere-transaction-base-seata-at in your local project, you can try to rewrite a seata at integration module in your local project. Long story short, you need

1. Implement org.apache.shardingsphere.transaction.spi.ShardingSphereDistributionTransactionManager and org.apache.shardingsphere.infra.executor.sql.hook.SQLExecutionHook
2. The implementation of org.apache.shardingsphere.transaction.spi.ShardingSphereDistributionTransactionManager#getType() should return BASE to avoid the unit test failure mentioned in Fixes for unjudged Seata AT transactions caused by #30462 #30474.