Merge pull request #13960 from hrdinka/fix/communi-desktop

communi: fix .desktop file's `Exec` path

pkgs/applications/networking/irc/communi/default.nix

···
 
   postInstall = ''
     wrapQtProgram "$out/bin/communi"
+    substituteInPlace "$out/share/applications/communi.desktop" \
+      --replace "/usr/bin" "$out/bin"
   '';
 
   meta = with stdenv.lib; {