GIT_SILENT Update Appstream for new release

(cherry picked from commit e51a607b)

org.kde.Help.appdata.xml

@@ -302,9 +302,9 @@
   </provides>
   <launchable type="desktop-id">org.kde.Help.desktop</launchable>
   <releases>
+    <release version="5.7.6.21121" date="2022-01-06"/>
     <release version="5.7.6.21120" date="2021-12-09"/>
     <release version="5.7.6.21083" date="2021-11-04"/>
     <release version="5.7.6.21082" date="2021-10-07"/>
-    <release version="5.7.6.21081" date="2021-09-02"/>
   </releases>
 </component>