GIT_SILENT Update Appstream for new release

org.kde.kolourpaint.appdata.xml

@@ -383,9 +383,9 @@
     <binary>kolourpaint</binary>
   </provides>
   <releases>
+    <release version="21.08.3" date="2021-11-04"/>
     <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"/>
   </releases>
 </component>