Ensure Symfony/mbstring-polyfill version 1.31 or higher (#376)

Author: ellnix

composer.json

@@ -15,7 +15,8 @@
         "illuminate/support": "^10.20|^11.0",
         "laravel/prompts": "^0.1.18|^0.2.0|^0.3.0",
         "symfony/console": "^6.2|^7.0",
-        "symfony/process": "^6.2|^7.0"
+        "symfony/process": "^6.2|^7.0",
+        "symfony/polyfill-mbstring": "^1.31"
     },
     "require-dev": {
         "phpstan/phpstan": "^1.10",