[libadwaita/wip/exalm/migration-typo] doc: Fix typo in the migration guide

[Alexander Mikhaylenko <alexm src gnome org>]

commit 886a4ee27f35c42db0f8684422bd3f33f41eb247
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Fri Sep 10 21:01:06 2021 +0500

    doc: Fix typo in the migration guide

 doc/migrating-libhandy-1-4-to-libadwaita.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/doc/migrating-libhandy-1-4-to-libadwaita.md b/doc/migrating-libhandy-1-4-to-libadwaita.md
index d48f5d36..fd0973c7 100644
--- a/doc/migrating-libhandy-1-4-to-libadwaita.md
+++ b/doc/migrating-libhandy-1-4-to-libadwaita.md
@@ -397,7 +397,7 @@ If multiple linked groups were used to separate different groups of actions,
 insert extra spacing as follows:
 
 ```xml
-<object name="GtkSeparator">
+<object class="GtkSeparator">
   <style>
     <class name="spacer"/>
   </style>