Consider dropping/changing font dependency

Description:

GTK does not depend on any specific font.

Arch packaging is depending on cantarell-fonts, which GTK only uses internally as a reference.

If this is done simply to appease a typical Gnome environment, that default is now adwaita-fonts.

Regardless, the Cantarell font is unused on the system and non-required by any other packages:

$ pactree -r -d1 cantarell-fonts
cantarell-fonts
├─gtk3
└─gtk4

As this is cruft, I remove the dependency when I rebuild GTK3/4 (without the X11 backend).

Please consider either:

1. Dropping the font dependency altogether (ala Fedora) and relying on fontconfig.

-or-

2. Changing the font dependency to adwaita-fonts to match Gnome.