Allow Drush 13 for testing Drupal 11 (#759)

Author: mglaman

composer.json

@@ -21,7 +21,7 @@
         "behat/mink": "^1.8",
         "composer/installers": "^1.9",
         "drupal/core-recommended": "^10",
-        "drush/drush": "^10.0 || ^11 || ^12",
+        "drush/drush": "^10.0 || ^11 || ^12 || ^13@beta",
         "phpstan/extension-installer": "^1.1",
         "phpstan/phpstan-strict-rules": "^1.0",
         "phpunit/phpunit": "^8.5 || ^9",