feat(linux)!: Support streaming through XDG portals and Pipewire (#4417)

Co-authored-by: Carlos Garnacho <carlosg@gnome.org>
Co-authored-by: Carson Katri <Carson.katri@gmail.com>
Co-authored-by: Bond <bond-d@ukr.net>
Co-authored-by: d.bondarev <d.bondarev@crm-onebox.com>
Co-authored-by: Conn O'Griofa <connogriofa@gmail.com>

packaging/linux/dev.lizardbyte.app.Sunshine.metainfo.xml

@@ -33,10 +33,6 @@
       <code>flatpak run --command=additional-install.sh @PROJECT_FQDN@</code>
     </p>
     <p>NOTE: Sunshine uses a self-signed certificate. The web browser will report it as not secure, but it is safe.</p>
-    <p>NOTE: KMS Grab (Flatpak)</p>
-    <p>
-      <code>sudo -i PULSE_SERVER=unix:/run/user/$(id -u $whoami)/pulse/native flatpak run @PROJECT_FQDN@</code>
-    </p>
   </description>
 
   <releases>