gtk3x: Link against gtk-3.98.4
Make gtk3x-client to build against gtk-3.98.4.
It has turned out that gtk development versions towards gtk-4.0.0 had compatibility breaks even between point releases. Such a break is between 3.98.3 and 3.98.4. We need to specifically switch from 3.98.3 to 3.98.4.
Following patches need to be pushed at the same time with this: