[feature request] Make cachebackend can be reused by different jobs

[zjchenn]

What would you like to be added: Enable the CacheBackend created by the previous Job can be reused by the next Job.

Why is this needed: Users can avoid creating cacheBackend repeatedly and skip the step of caching remote files, thus improving the efficiency of cacheBackend.

[zjchenn]

Hi, I think this feature can make CacheBackend more useful. And my preliminary design is in this PR, looking forward to discussing with you!