Merge topic 'ci-macos-qt-6.9.3'

3f21bf9f0a ci: Restore packaging with macOS SDK from Xcode
c1ee4d57dc Utilities/Release: Remove unused Qt 5.15.2 build script for macOS
0f18aa010e ci: Update to Qt 6.9.3 on macOS
2ae318bb5d cmake-gui: Install only necessary plugins for Qt 6
74dec2c7fd cmake-gui: Detect Qt lib directory on macOS more robustly
0d1321770d cmake-gui: Clarify signature of QCheckBox::checkStateChanged callbacks
a49e5c8eb9 Utilities/Release: Teach macOS notarization script to sign Qt artifacts

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !11386