[calls] main-window: Fix the action name for the about dialog

[Evangelos Ribeiro Tzaras <devrtz src gnome org>]

commit 241909c9420a98969ca9439fb25ec47c3513d833
Author: Evangelos Ribeiro Tzaras <evangelos tzaras puri sm>
Date:   Thu Jul 15 11:05:00 2021 +0200

    main-window: Fix the action name for the about dialog

 src/ui/main-window.ui | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/ui/main-window.ui b/src/ui/main-window.ui
index 597c4920..a1baec0b 100644
--- a/src/ui/main-window.ui
+++ b/src/ui/main-window.ui
@@ -251,7 +251,7 @@
           <object class="GtkModelButton">
             <property name="visible">True</property>
             <property name="text" translatable="yes">_About Calls</property>
-            <property name="action-name">app.about</property>
+            <property name="action-name">win.about</property>
           </object>
         </child>