xed.desktop: Add application/x-zerosize mimetype.

ref: linuxmint/mint22-beta#26
ref: https://gitlab.gnome.org/GNOME/glib/-/merge_requests/3053

Author: mtwebster

data/xed.desktop.in.in

@@ -5,7 +5,7 @@ Exec=xed %U
 Terminal=false
 Type=Application
 StartupNotify=true
-MimeType=text/plain;
+MimeType=text/plain;application/x-zerosize;
 Icon=accessories-text-editor
 Categories=GTK;Utility;TextEditor;
 Keywords=text;editor;tabs;highlighting;code;multiple;files;pluggable;notepad;