[gnome-builder] meson-templates: add GTK 4 requirement to interface

[Christian Hergert <chergert src gnome org>]

commit 864cc85892adb387e42a11b00149b0d65f3894cf
Author: Christian Hergert <chergert redhat com>
Date:   Sun Nov 28 10:36:34 2021 -0800

    meson-templates: add GTK 4 requirement to interface
    
    Unfortunately this does practically nothing to help us from the Glade
    standpoint as it does not stop itself from loading even when this is set.
    
    Related #1575

 src/plugins/meson-templates/resources/src/window-gtk4.ui | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/src/plugins/meson-templates/resources/src/window-gtk4.ui 
b/src/plugins/meson-templates/resources/src/window-gtk4.ui
index 67adc8375..329af3f3a 100644
--- a/src/plugins/meson-templates/resources/src/window-gtk4.ui
+++ b/src/plugins/meson-templates/resources/src/window-gtk4.ui
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <interface>
+  <requires lib='gtk' version='4.0'/>
   <template class="{{PreFix}}Window" parent="GtkApplicationWindow">
     <property name="default-width">600</property>
     <property name="default-height">300</property>