Fix journal storage handling in windows

[hrntsm]

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Reference Issues/PRs

optuna/optuna#4308

What does this implement/fix? Explain your changes.

In windows environment, if lock_obj is not specified explicitly, the same error as reference will occur when handling JournalStorage, so os is determined and lock_obj is included in the argument.

This is probably why the human-in-the-loop optimization does not work because the change to the journal storage cannot be performed.

[codecov]

Codecov Report

Attention: 28 lines in your changes are missing coverage. Please review.

Comparison is base (1203501) 68.22% compared to head (5d3989a) 68.20%.
Report is 196 commits behind head on main.

❗ Current head 5d3989a differs from pull request most recent head 02999c7. Consider uploading reports for the commit 02999c7 to get more accurate results

Files	Patch %	Lines
optuna_dashboard/artifact/_backend.py	31.42%	24 Missing ⚠️
optuna_dashboard/_app.py	94.59%	2 Missing ⚠️
optuna_dashboard/_storage_url.py	66.66%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #742      +/-   ##
==========================================
- Coverage   68.22%   68.20%   -0.02%     
==========================================
  Files          35       35              
  Lines        2329     2334       +5     
==========================================
+ Hits         1589     1592       +3     
- Misses        740      742       +2     

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[c-bata]

LGTM.