Fix: Can handle negative coordinates with Spatialite

[adrien-berchet]

Description

Fixes #516

Checklist

This pull request is:

• [ ] A documentation / typographical error fix
  • Good to go, no issue or tests are needed
• [x] A short code fix
  • [x] Please include: Fixes: #<issue number> in the description if it solves an existing issue (which must include a complete example of the issue).
  • [x] Please include tests that fail with the main branch and pass with the provided fix.
• [ ] A new feature implementation or update an existing feature
  • [ ] Please include: Fixes: #<issue number> in the description if it solves an existing issue (which must include a complete example of the feature).
  • [ ] Please include tests that cover every lines of the new/updated feature.
  • [ ] Please update the documentation to describe the new/updated feature.