[String] Added a help message when translation-contracts is not installed

Author: lyrixx

Slugger/AsciiSlugger.php

@@ -15,6 +15,10 @@
 use Symfony\Component\String\UnicodeString;
 use Symfony\Contracts\Translation\LocaleAwareInterface;
 
+if (!interface_exists(LocaleAwareInterface::class)) {
+    throw new \LogicException('You cannot use the "Symfony\Component\String\Slugger\AsciiSlugger" as the "symfony/translation-contracts" package is not installed. Try running "composer require symfony/translation-contracts".');
+}
+
 /**
  * @author Titouan Galopin <[email protected]>
  *