columnview: Underallocation spew
When resizing a column to be too small for its content, we do the right thing and prevent overdraw by setting overflow to HIDDEN. But we still allocate the cell too small, and that gets us lots of:
(gtk4-demo:22044): Gtk-CRITICAL **: 21:09:36.357: Allocation width too small. Tried to allocate 96x25, but GtkColumnViewTitle 0x1249c50 needs at least 108x25. (gtk4-demo:22044): Gtk-CRITICAL **: 21:09:36.373: Allocation width too small. Tried to allocate 54x25, but GtkColumnViewTitle 0x1249de0 needs at least 67x25.