graphics/qgis: Update to 3.42.3

• Add previously forgotten CMAKE_ON=WITH_QTWEBENGINE

Changelog: https://github.com/qgis/QGIS/compare/final-3_42_2%5E...final-3_42_3

Reported by: portscout, Repology
MFH: 2025Q2

(cherry picked from commit 43b8a730357ea37d25292712b3e8bcc022841d53)