Fix security/* cross-dependencies

Author: nicolas-grekas

composer.json

@@ -30,7 +30,7 @@
         "symfony/templating": "~2.1|~3.0.0",
         "symfony/translation": "~2.7|~3.0.0",
         "symfony/yaml": "^2.0.5|~3.0.0",
-        "symfony/security": "~2.6|~3.0.0",
+        "symfony/security": "^2.8.31|^3.3.13",
         "symfony/security-acl": "~2.6|~3.0.0",
         "symfony/stopwatch": "~2.2|~3.0.0",
         "symfony/console": "~2.8|~3.0.0",