package/qt6: bump version to 6.4.3
For details see [1].
[1] https://code.qt.io/cgit/qt/qtreleasenotes.git/about/qt/6.4.3/release-note.md
Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit a8467289111843e070816c9ffb2004baa74ffead)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>