fix: validation in methods

Fixed error when validating method names. Now it will throw exception if it is an empty string.

Author: josantonius

src/ExceptionHandler.php

@@ -43,7 +43,7 @@ public function __construct(
 
         $methodNames = array_merge($runBeforeCallback, $runAfterCallback);
 
-        if (array_filter($methodNames, fn ($method) => !is_string($method))) {
+        if (array_filter($methodNames, fn ($method) => (!is_string($method) || $method = ''))) {
             throw new WrongMethodNameException();
         }