fix: download file will throw error when dir is empty

[jiuker]

Summary

Details

if we run client like this client.download_file("dir/to-copy.py", "to-copy.py")
will got this

  File "/mnt/d/workspace/pythong/venv/lib/python3.12/site-packages/multistorageclient/providers/s3.py", line 751, in _download_file
    os.makedirs(os.path.dirname(f), exist_ok=True)
  File "<frozen os>", line 225, in makedirs
FileNotFoundError: [Errno 2] No such file or directory: ''

Usage

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Additional Information

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[commiterate]

Need a rebase so the check workflow runs (bug in our GHA definitions).

[jiuker]

Need a rebase so the check workflow runs (bug in our GHA definitions).

Rebased

[commiterate]

Looks like some flakiness with the order glob returns stuff on the GitHub Actions runners. I'll pull this locally to test.

[commiterate]

Passed. Mirroring the PR internally (moving development to GitHub is the plan later on).

[commiterate]

Internally mirrored PR merged. Merged commit ID is 0a5e65874399b339c6ec0a3def6f2c5ebbd8f2b7.

This will be mirrored back to GitHub on the next release.

Note the author information will be wrong due to GitLab making the merging user the squashed + merged commit's author.