[sysprof/wip/gtk4-port] tab: fix spacing

[Christian Hergert <chergert src gnome org>]

commit 6889a247f2d5a81605b8f5c29daa7b1824b3ba12
Author: Christian Hergert <chergert redhat com>
Date:   Fri Oct 1 13:57:14 2021 -0700

    tab: fix spacing

 src/libsysprof-ui/sysprof-tab.ui | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/src/libsysprof-ui/sysprof-tab.ui b/src/libsysprof-ui/sysprof-tab.ui
index c07d5cf8..f57f717d 100644
--- a/src/libsysprof-ui/sysprof-tab.ui
+++ b/src/libsysprof-ui/sysprof-tab.ui
@@ -2,7 +2,6 @@
 <interface>
   <template class="SysprofTab" parent="GtkWidget">
     <property name="hexpand">true</property>
-    <property name="spacing">6</property>
     <child>
       <object class="GtkCenterBox" id="center_box">
         <child type="start">
@@ -16,6 +15,8 @@
         </child>
         <child type="center">
           <object class="GtkLabel" id="title">
+            <property name="margin-start">6</property>
+            <property name="margin-end">6</property>
           </object>
         </child>
         <child type="end">