GIT_SILENT Update Appstream for new release

(cherry picked from commit 4991ea23)

org.kde.bovo.appdata.xml

@@ -133,10 +133,10 @@
     <binary>bovo</binary>
   </provides>
   <releases>
+    <release version="21.04.2" date="2021-06-10"/>
     <release version="21.04.1" date="2021-05-13"/>
     <release version="21.04.0" date="2021-04-22"/>
     <release version="20.12.3" date="2021-03-04"/>
-    <release version="20.12.2" date="2021-02-04"/>
   </releases>
   <content_rating type="oars-1.1"/>
 </component>