GIT_SILENT Update Appstream for new release

(cherry picked from commit e77b4861)

org.kde.kolourpaint.appdata.xml

@@ -383,9 +383,9 @@
     <binary>kolourpaint</binary>
   </provides>
   <releases>
+    <release version="20.08.2" date="2020-10-08"/>
     <release version="20.08.1" date="2020-09-03"/>
     <release version="20.08.0" date="2020-08-13"/>
     <release version="20.04.3" date="2020-07-09"/>
-    <release version="20.04.2" date="2020-06-11"/>
   </releases>
 </component>