Fix `scipy` and `svg.path` dependency issue

[DunklesArchipel]

Checklist

• [x] Added an entry in doc/news/.
• [o] Added a test for this change.
• [o] Updated the documentation.

[DunklesArchipel]

@saraedum the conversation in https://github.com/conda-forge/svgdigitizer-feedstock/pull/21 it was not conclusive, but I guess we should include these two modules again.