Do not echo headers in login/register request response

[aeneasr]

Describe the bug

Right now when fetching the login or registration request, we recieve a list of headers:

{
  id: '877c1520-e638-4b90-9c89-22ed10de3b5d',
  issued_at: '2019-10-24T11:22:25.56823Z',
  expires_at: '2019-10-24T11:32:25.56823Z',
  request_url: 'http://api.cloud.ory.local/auth/browser/registration',
  headers: {
    Accept: [
      'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8'
    ],
    'Accept-Encoding': [ 'gzip, deflate' ],
    'Accept-Language': [ 'de,en-US;q=0.7,en;q=0.3' ],
    'Cache-Control': [ 'max-age=0' ],
    Cookie: [
      'csrf_token=KJOz6YZgHVLJOLqgYFATHHjhzAHxiPnNM5CRPOLeCho=; ajs_user_id=null; ajs_group_id=null; ajs_anonymous_id=%2253a846e9-0bf9-4981-aa88-b3f140ea4641%22; hive_session_manager=MTU3MTg0OTAzNnxEdi1CQkFFQ180SUFBUkFCRUFBQVFmLUNBQUVHYzNSeWFXNW5EQVVBQTNOcFpBWnpkSEpwYm1jTUpnQWtaV05sWW1Ga1l6Z3RPREkxTnkwME9UZzRMV0l3WlRFdFlURmpaalUyWTJZNE9XVmp817Fnc_NTTpPyo4geGsizplvDKFgAbeWWTofX2DbGapQ='
    ],
    'Upgrade-Insecure-Requests': [ '1' ],
    'User-Agent': [
      'Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:69.0) Gecko/20100101 Firefox/69.0'
    ],
    'X-Forwarded-For': [ '192.168.64.1' ],
    'X-Forwarded-Host': [ 'api.cloud.ory.local' ],
    'X-Forwarded-Port': [ '80' ],
    'X-Forwarded-Proto': [ 'http' ],
    'X-Original-Uri': [
      '/projects/late-nigh-test-8zk4kcxoh5yd7kr0/services/hive/public/auth/browser/registration'
    ],
    'X-Real-Ip': [ '192.168.64.1' ],
    'X-Request-Id': [ '28091f6b1ab94061fdd28463226134e4' ],
    'X-Scheme': [ 'http' ]
  },
  active: 'password',
  methods: {
    oidc: { method: 'oidc', config: [Object] },
    password: { method: 'password', config: [Object] }
  }
}

Expected behavior

Omit this data.