Make sure gpuclockctl inherits the DISPLAY and XAUTHORITY variables so nvidia-settings works

data/com.feralinteractive.GameMode.policy.in

@@ -32,6 +32,7 @@
       <allow_active>yes</allow_active>
     </defaults>
     <annotate key="org.freedesktop.policykit.exec.path">@LIBEXECDIR@/gpuclockctl</annotate>
+    <annotate key="org.freedesktop.policykit.exec.allow_gui">true</annotate>
   </action>
 
 </policyconfig>