Fix a bunch of pytest warnings

[simonw]

Refs:

• So many warnings in pytest -Wall #692

---

📚 Documentation preview 📚: https://sqlite-utils--693.org.readthedocs.build/en/693/

[codecov]

Codecov Report

❌ Patch coverage is 91.42857% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 95.20%. Comparing base (066d0f3) to head (50a979b).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
sqlite_utils/cli.py	92.77%	6 Missing ⚠️
sqlite_utils/db.py	50.00%	2 Missing ⚠️
sqlite_utils/utils.py	94.44%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #693      +/-   ##
==========================================
- Coverage   95.34%   95.20%   -0.14%     
==========================================
  Files           8        8              
  Lines        3007     3088      +81     
==========================================
+ Hits         2867     2940      +73     
- Misses        140      148       +8     

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[simonw]

OK wow, Claude Code just crunched through the rest of the warnings as well: https://gistpreview.github.io/?0bb8e869b82f6ff0db647de755182502