Qt: Update Qt 6 to 6.4.2

As a patch release, Qt 6.4.2 does not introduce any new features but
contains ~ 150 bug fixes, security updates, and other improvements to
the top of the Qt 6.4.1 release. See more information about the most
important changes and bug fixes from Qt 6.4.2 release note.

Announcement: https://www.qt.io/blog/qt-6.4.2-released
Release Notes: https://code.qt.io/cgit/qt/qtreleasenotes.git/about/qt/6.4.2/release-note.md