fix: can't print log because the tracing guard is dropped

[zyy17]

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Refer to a related PR or issue link (optional)

What's changed and what's your intention?

The bug is caused by #3981.

It's a fast fix for adding guard in Instance to avoid dropping.

I think the elegant way to resolve the problem is to refactor the init_global_logging(), split it into multiple functions, and initialize it at the beginning of main().

We should release the new version of db after the PR is merged. Fortunately, it's not in the v0.8.0.

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.

[codecov]

Codecov Report

Attention: Patch coverage is 47.05882% with 27 lines in your changes are missing coverage. Please review.

Project coverage is 85.20%. Comparing base (4778575) to head (8c5efe2).
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4005      +/-   ##
==========================================
- Coverage   85.50%   85.20%   -0.30%     
==========================================
  Files         977      977              
  Lines      169344   169360      +16     
==========================================
- Hits       144793   144304     -489     
- Misses      24551    25056     +505     

[WenyXu]

Let's run make fmt