[GTK] Allow buttons to be 0/0 on Gtk 4.x

Author: akurtakov

bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/swt_theming_fixes_gtk_4_0_0.css

@@ -1,3 +1,7 @@
 button.toggle {
 	padding: 0px;
 }
+button {
+	min-height: 0px;
+	min-width: 0px;
+}