GIT_SILENT Update Appstream for new release

(cherry picked from commit b4447aa9)

src/data/org.kde.kleopatra.appdata.xml

@@ -154,9 +154,9 @@
     <binary>kleopatra</binary>
   </provides>
   <releases>
+    <release version="3.1.16.210840" date="2021-08-12"/>
     <release version="3.1.15.210403" date="2021-07-08"/>
     <release version="3.1.15.210402" date="2021-06-10"/>
     <release version="3.1.15.210401" date="2021-05-13"/>
-    <release version="3.1.15.210400" date="2021-04-22"/>
   </releases>
 </component>