`signup` query should not need `authorization`

[hyochan]

I've tried signup query locally and it needs authentication.

Server running on port 4000
Error: Not authorized
    at C:\Users\dooboolab\Documents\Github\dooboolab\talktalk-node\src\middlewares/authMiddleware.js:33:13
    at process.internalTickCallback (internal/process/next_tick.js:77:7)

Tried query.

mutation {
    signup (
    email: "aa@aa.aa"
    password: "password"
    name: "test"
  ) {
    user{
      name
    }
    token
  }
}