Update sip, pyqt-builder and pyqt-sip modules

[github-actions[bot]]

sip: Update sip-6.8.3.tar.gz to 6.8.6 pyqt-builder: Update pyqt_builder-1.16.2.tar.gz to 1.16.4 pyqt-sip: Update PyQt5_sip-12.13.0.tar.gz to 12.15.0

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[flathubbot]

Started test build 134257

[flathubbot]

Build 134257 failed