[core] Fix the error message when storage is not set.

[fishbone]

Signed-off-by: Yi Cheng 74173148+iycheng@users.noreply.github.com

Why are these changes needed?

Due to incorrect setup, storage is passed even it's None and in the worker it'll be treated as "None" instead of None and thus it'll give wrong error message which mislead the users.

This PR fixed it by passing the storage only when it's setup.

Related issue number

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  • This PR is not tested :(

[fishbone]

@scv119 @suquark could you take a look at this? I think it should be included in 2.4 release.

[suquark]

@iycheng This is nice catch & nice fix! Thanks a lot!