fix version

Author: somas95

flatpak/de.wolfvollprecht.UberWriter.appdata.xml

@@ -28,7 +28,7 @@
     </screenshot>
   </screenshots>
   <releases>
-    <release date="2019-03-10" version="2.1.5-beta2">
+    <release date="2019-03-10" version="2.1.5">
       <description>
         <ul>
           <li>Added italian language</li>