[gnome-builder/wip/gtk4-port] plugins/testui: tweak spacing

[Christian Hergert <chergert src gnome org>]

commit 1da2cfb368162e67a0b54c9c2a1e9263b9a5b109
Author: Christian Hergert <chergert redhat com>
Date:   Thu Jun 30 17:57:01 2022 -0700

    plugins/testui: tweak spacing
    
    This makes it feel closer to what project files has.

 src/plugins/testui/gbp-testui-panel.ui | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/src/plugins/testui/gbp-testui-panel.ui b/src/plugins/testui/gbp-testui-panel.ui
index 94318ba90..44b55436d 100644
--- a/src/plugins/testui/gbp-testui-panel.ui
+++ b/src/plugins/testui/gbp-testui-panel.ui
@@ -29,10 +29,10 @@
         <property name="child">
           <object class="GtkBox">
             <property name="spacing">6</property>
-            <property name="margin-top">3</property>
-            <property name="margin-bottom">3</property>
-            <property name="margin-start">3</property>
-            <property name="margin-end">3</property>
+            <property name="margin-top">4</property>
+            <property name="margin-bottom">4</property>
+            <property name="margin-start">6</property>
+            <property name="margin-end">6</property>
             <child>
               <object class="GtkImage">
                 <binding name="icon-name">