fix $events docblock type (#53808)

`Illuminate\Contracts\Events\Dispatcher` is the correct name of the imported interface that is type-hinted in the constructor

src/Illuminate/Log/Context/Repository.php

@@ -22,7 +22,7 @@ class Repository
     /**
      * The event dispatcher instance.
      *
-     * @var \Illuminate\Events\Dispatcher
+     * @var \Illuminate\Contracts\Events\Dispatcher
      */
     protected $events;