[Development] Qt 6 buildsystem support requirements

[Kevin Kofler]

Thiago Macieira wrote:
> Specifically, the problem with TensorFlow is that it wants to download its
> dependencies when you compile it, then compile them at the same time. That
> can't work because the build servers don't have internet connectivity.

+1, this is also a hard, non-negotiable requirement in Fedora. Any build 
system that requires downloading dependencies at build time is a complete 
non-starter. The builds would just fail with no way to fix them.

        Kevin Kofler