Updated phpro/grumphp dependency

Author: jbekaert-makeitfly

composer.json

@@ -4,7 +4,7 @@
   "description": "GrumPHP + tools for Drupal",
   "require": {
     "composer-plugin-api": "^2.0",
-    "phpro/grumphp": "^1.0",
+    "phpro/grumphp": "^2.0",
     "squizlabs/php_codesniffer": "^3.4",
     "phpstan/phpstan": "^1.2",
     "drupal/coder": "^8.3",