Allow Symfony 5.0

Author: nicolas-grekas

composer.json

@@ -19,7 +19,7 @@
         "php": "^7.1.3"
     },
     "require-dev": {
-        "symfony/process": "~3.4|~4.0"
+        "symfony/process": "^3.4|^4.0|^5.0"
     },
     "autoload": {
         "psr-4": { "Symfony\\Component\\Dotenv\\": "" },