Use single-quotes in SQL string in detect_spatialite(), Fixes #2473

[asg017]

Newer version of SQLite may reject strings that use double quotes, as seen in #2473

Should also check other SQL in this codebase, but this solves the immediate issue

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📚 Documentation preview 📚: https://datasette--2474.org.readthedocs.build/en/2474/

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.42%. Comparing base (7945f4f) to head (5e6b890).
⚠️ Report is 194 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2474      +/-   ##
==========================================
+ Coverage   90.37%   90.42%   +0.04%     
==========================================
  Files          41       41              
  Lines        6474     6474              
==========================================
+ Hits         5851     5854       +3     
+ Misses        623      620       -3     

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