py-contourpy: update to 1.2.1.

ContourPy 1.2.1 is a compatibility release to support NumPy 2.

This release supports Python 3.9 to 3.12.

Thanks to new contributor @motoro and core maintainer @ianthomas23.

Compatibility:

    Support NumPy 2 (#331, #371, #372)

Code improvements:

    Fix a few f-strings (#332)

Documentation improvements:

    Clarify use of quotes in pip install (#349)

Build, testing and CI improvements:

    Improved linting (#322, #323, #333, #337)
    Update cppcheck to 2.11 (#324)
    Support running tests on unicore hosts (#327)
    Improved tests against nightly wheels (#329, #373)
    Update to chromium 118 for Bokeh renderer tests (#325)
    Add CI run using earliest supported numpy (#347)

(wiz)