remove duplicated dependency from composer.json

Author: eugene-matvejev

composer.json

@@ -23,7 +23,6 @@
     "require": {
         "php": ">= 5.5.9",
         "leafo/lessphp": "^0.5",
-        "leafo/scssphp": "0.6.3 as dev-master",
         "leafo/scssphp-compass": "dev-master"
     },
     "require-dev": {