chore: upgrade to L9

BREAKING CHANGE: This commit updates the Laravel framework to version 9. Additionally, it also updates outdated and abandoned dependencies in the composer.json file.

The resources/lang directory has also been moved to the repository's root directory.

app/Http/Requests/ChangePasswordRequest.php

@@ -44,7 +44,7 @@ class ChangePasswordRequest extends FormRequest
     {
         return [
             'newPassword' => 'required|string|confirmed',
-            'oldPassword' => 'required|string|password',
+            'oldPassword' => 'required|string|current_password',
         ];
     }
 }