Remove "extra"

ibaciulis · ibaciulis · commit 4cd76446a72d · 2019-02-08T18:02:23.000+02:00
diff --git a/composer.json b/composer.json
@@ -28,10 +28,5 @@
   },
   "require-dev": {
     "omnipay/tests": "^3.0"
-  },
-  "extra": {
-    "branch-alias": {
-      "dev-master": "2.0.x-dev"
-    }
   }
 }
