Qt6: Update to 6.5.3

As a patch release, Qt 6.5.3 does not introduce any new features but
contains more than 500 bug fixes, security updates, and other
improvements on top of Qt 6.5.2 release. See more information about
the most important changes and bug fixes from Qt 6.5.3 release note.

Annoucement: https://www.qt.io/blog/qt-6.5.3-released
Release note: https://code.qt.io/cgit/qt/qtreleasenotes.git/about/qt/6.5.3/release-note.md