fix contributors url

Author: Philipp Kübler

README.md

@@ -242,7 +242,7 @@ composer lint:phpmd
 This package is heavily inpsired by [Spatie / laravel-permission](https://github.com/spatie/laravel-permission).
 
 - [Philipp Kübler](https://github.com/pkuebler)
-- [All Contributors](../../contributors)
+- [All Contributors](https://github.com/sourceboat/laravel-static-permission/graphs/contributors)
 
 ## License