github-login: move comment to default.js

Signed-off-by: kamijin_fanta <kamijin@live.jp>

config.json.example

@@ -50,7 +50,6 @@
             "consumerSecret": "change this"
         },
         "github": {
-            "enterpriseURL": "if you use github.com, not need to specify",
             "clientID": "change this",
             "clientSecret": "change this"
         },

lib/config/default.js

@@ -104,7 +104,7 @@ module.exports = {
     consumerSecret: undefined
   },
   github: {
-    enterpriseURL: undefined,
+    enterpriseURL: undefined, // if you use github.com, not need to specify
     clientID: undefined,
     clientSecret: undefined
   },