New QT6 components

[Benoît Minisini <benoit.minisini@xxxxxxxxxxxxxxxx>]

Hi,

New Qt6 components are now available in the "master" branch.

Only the "ubuntu-lunar" build of the GitLab pipeline tries to compile 
qt6. I will update the other systems as soon as I find then name of the 
needed Qt6 packages.

At the same time, a new problem arises with clang that could not compile 
Gambas anymore. It breaks the "archlinux-clang" build, and so the 
pipeline will be in failed state until I understand how I must rewrite 
the C code so that clang accepts it.

Regards,

--
Benoît Minisini.