GIT_SILENT Update Appstream for new release

(cherry picked from commit 23dec95c)

org.kde.ktouch.appdata.xml

@@ -228,9 +228,9 @@
   </provides>
   <content_rating type="oars-1.0"/>
   <releases>
+    <release version="21.08.2" date="2021-10-07"/>
     <release version="21.08.1" date="2021-09-02"/>
     <release version="21.08.0" date="2021-08-12"/>
     <release version="21.04.3" date="2021-07-08"/>
-    <release version="21.04.2" date="2021-06-10"/>
   </releases>
 </component>