[gnome-shell] extensions-app: Change lists style class to `.boxed-list`

[Marge Bot <marge-bot src gnome org>]

commit db39b792c21846dc3ffd40b2115c68c55c104717
Author: Romain Vigier <romain romainvigier fr>
Date:   Tue Jan 18 11:37:51 2022 +0100

    extensions-app: Change lists style class to `.boxed-list`
    
    The previous `.content` style class is deprecated.
    
    Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2114>

 subprojects/extensions-app/data/ui/extensions-window.ui | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/subprojects/extensions-app/data/ui/extensions-window.ui 
b/subprojects/extensions-app/data/ui/extensions-window.ui
index e4f12708ee..88e0f1173c 100644
--- a/subprojects/extensions-app/data/ui/extensions-window.ui
+++ b/subprojects/extensions-app/data/ui/extensions-window.ui
@@ -101,7 +101,7 @@
                           <object class="GtkListBox" id="userList">
                             <property name="selection-mode">none</property>
                             <style>
-                              <class name="content"/>
+                              <class name="boxed-list"/>
                             </style>
                           </object>
                         </child>
@@ -114,7 +114,7 @@
                           <object class="GtkListBox" id="systemList">
                             <property name="selection-mode">none</property>
                             <style>
-                              <class name="content"/>
+                              <class name="boxed-list"/>
                             </style>
                           </object>
                         </child>