chore: add backslash

Author: adhocore

src/JWT.php

@@ -83,7 +83,7 @@ public function __construct($key, $algo = 'HS256', $maxAge = 3600, $leeway = 0,
 
         if (\is_array($key)) {
             $this->registerKeys($key);
-            $key = reset($key); // use first one!
+            $key = \reset($key); // use first one!
         }
 
         $this->key        = $key;
@@ -233,7 +233,7 @@ protected function verify($input, $signature)
     protected function urlSafeEncode($data)
     {
         if (\is_array($data)) {
-            $data = \json_encode($data, JSON_UNESCAPED_SLASHES);
+            $data = \json_encode($data, \JSON_UNESCAPED_SLASHES);
             $this->validateLastJson();
         }