Update matplotlib to 3.9.1.post1#351

pyup-bot wants to merge 4 commits intomasterRexGalilae/vasp-tools:masterfrom

pyup-update-matplotlib-3.0.2-to-3.9.1.post1RexGalilae/vasp-tools:pyup-update-matplotlib-3.0.2-to-3.9.1.post1Copy head branch name to clipboard