Fix exception cause in storage.py (#90118)
This change causes the correct message to be shown between the two tracebacks when an error is shown.
More context here: https://blog.ram.rachum.com/post/621791438475296768/improving-python-exception-chaining-with
Pull Request resolved: https://github.com/pytorch/pytorch/pull/90118
Approved by: https://github.com/kit1980
