[Load][Bug] load channel manager add batch with unknown load id: xxx

[morningman]

Describe the bug
When performing a long-time load job, the following errors may occur. Causes the load to fail.

load channel manager add batch with unknown load id: xxx

There is a case of this error because Doris opened an unrelated channel during the load
process. This channel will not receive any data during the entire load process. Therefore,
after a fixed timeout, the channel will be released.

And after the entire load job is completed, it will try to close all open channels. When it try to
close this channel, it will find that the channel no longer exists and an error is reported.