[5.4] Fix auto-registration for autoupdates for new installs (joomla#45754)

Auto-Update registration state is correctly stored in the config.

Author: SniperSister

administrator/components/com_joomlaupdate/src/Model/UpdateModel.php

@@ -632,7 +632,7 @@ public function changeAutoUpdateRegistration(AutoupdateRegisterState $targetStat
             ($targetState === AutoupdateRegisterState::Subscribe)
                 ? AutoupdateRegisterState::Subscribed
                 : AutoupdateRegisterState::Unsubscribed,
-            ($targetState === AutoupdateRegisterState::Unsubscribed)
+            ($targetState === AutoupdateRegisterState::Subscribe)
         );
 
         return AutoupdateRegisterResultState::Success;