Update 3 modules

[github-actions[bot]]

Update libjxl.git to 0.9.1 Update webkitgtk-2.42.1.tar.xz to 2.42.5 Update libvips to 8.15.1

🤖 This pull request was automatically generated by flathub-infra/flatpak-external-data-checker. Please open an issue if you have any questions or complaints. 🤖

[flathubbot]

Started test build 97974