Add setPusher() to PusherBroadcaster::class (#37033)

Author: vdauchy

src/Illuminate/Broadcasting/Broadcasters/PusherBroadcaster.php

@@ -160,4 +160,15 @@ public function getPusher()
     {
         return $this->pusher;
     }
+
+    /**
+     * Set the Pusher SDK instance.
+     *
+     * @param \Pusher\Pusher $pusher
+     * @return void
+     */
+    public function setPusher($pusher)
+    {
+        $this->pusher = $pusher;
+    }
 }