* Catch exception in thread pool when migrate repos
* Add comment and use different exit code
* Check exception only
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Co-authored-by: 杨赫然 <heran.yang@seafile.com>
* Support migrate between different storages
* Don't use subquery to filter repo_id
* Modify variable names
Co-authored-by: 杨赫然 <heran.yang@seafile.com>