Update dependency twig/twig to v3 [SECURITY]

Author: renovate[bot]

composer.json

@@ -27,7 +27,7 @@
         "symfony/swiftmailer-bundle": "^2.3.10",
         "symfony/symfony": "3.3.*",
         "symfony/validator": "^3.3",
-        "twig/twig": "^1.0||^2.0",
+        "twig/twig": "3.26.0",
         "doctrine/doctrine-fixtures-bundle": "^2.4",
         "sensio/generator-bundle": "^3.0"
     },