Unpin test requirements

[marthacryan]

• Replaces the separated files which pinned different versions of packages for each version of python with two files that list the unpinned requirements for core / optional tests
• Updates the CI config to be more parameterized
• Removes the no numpy tests - it turns out that it wasn't actually testing without numpy, and since we added narwhals our tests do in fact fail without numpy
• Removes orca tests from config
• Adds uv into a couple of more spots to speed up the dependency downloads
• Removes unused commit step from plotly.js dev build job
• Removes unused import of ipython and sage salvus in plotly/tools.py

[emilykl]

@marthacryan LGTM once my final comments are addressed! 🚀

This is a huge win for maintainability.

A few big-picture thoughts that could be addressed in another PR:

• IMO we should bring back the no-numpy job (to prevent numpy dependency from accidentally slipping into core Plotly.py)

• If we're testing pandas<2 with Python 3.9, should we also test pandas<2 for other Python versions? Probably worth a discussion.