[gnome-music/wip/jfelder/playlistdialog-border] playlistdialog: Use margins instead of border-width property

[Jean Felder <jfelder src gnome org>]

commit b194db39397a2e3ce94ab692b8ea54b89402f536
Author: Jean Felder <jfelder src gnome org>
Date:   Thu Feb 3 00:34:42 2022 +0100

    playlistdialog: Use margins instead of border-width property
    
    This property does not exist in Gtk4 anymore.

 data/ui/PlaylistDialog.ui | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/data/ui/PlaylistDialog.ui b/data/ui/PlaylistDialog.ui
index 30e2384ab..655322c12 100644
--- a/data/ui/PlaylistDialog.ui
+++ b/data/ui/PlaylistDialog.ui
@@ -147,7 +147,10 @@
                       <object class="GtkBox" id="new-playlist-hbox">
                         <property name="visible">True</property>
                         <property name="can_focus">False</property>
-                        <property name="border_width">6</property>
+                        <property name="margin-bottom">6</property>
+                        <property name="margin-end">6</property>
+                        <property name="margin-start">6</property>
+                        <property name="margin-top">6</property>
                         <child>
                           <object class="GtkEntry" id="_new_playlist_entry">
                             <property name="visible">True</property>