title: Error on Credentials handshake of Public Test Environement
body: <p>I am seeing the following error on step 3 Credentials handshake of OCN Node registration. (<a href="https://shareandcharge.atlassian.net/wiki/spaces/OCN/pages/265945122/OCN+Node+registration#3.-Credentials-handshake" rel="nofollow noreferrer">https://shareandcharge.atlassian.net/wiki/spaces/OCN/pages/265945122/OCN+Node+registration#3.-Credentials-handshake</a>)</p>
  
  <p>When I send the credentials handshake, I see the following error:</p>
  
  <pre><code>{
    "status_code": 3001,
    "status_message": "Failed to request from https://edrv-ocpi-dev.herokuapp.com/ocpi/versions: Cannot deserialize instance of `snc.openchargingnetwork.node.models.ocpi.OcpiResponse&lt;java.util.List&lt;snc.openchargingnetwork.node.models.ocpi.Version&gt;&gt;` out of START_ARRAY token\n at [Source: (String)\"[{\"status_code\":1000,\"data\":{\"versions\":[{\"version\":\"2.2\",\"url\":\"https://edrv-ocpi-dev.herokuapp.com/ocpi/2.2\"}]},\"timestamp\":\"2020-02-15T07:48:58.364Z\"}]\"; line: 1, column: 1]",
    "timestamp": "2020-02-15T07:48:58.390914Z"
  }
  </code></pre>
  
  <p>This is the request I am sending:</p>
  
  <pre><code>curl -X POST \
   https://qa-client.emobilify.com/ocpi/2.2/credentials \
   -H 'Accept: */*' \
   -H 'Accept-Encoding: gzip, deflate' \
   -H 'Authorization: Token 21c158fc-****-****-****-************' \
   -H 'Cache-Control: no-cache' \
   -H 'Connection: keep-alive' \
   -H 'Content-Length: 297' \
   -H 'Content-Type: application/json' \
   -H 'Host: qa-client.emobilify.com' \
   -H 'Postman-Token: 8cb3bcba-2cc0-4923-9290-04be261fb686,fe8e2916-ee94-4676-a60a-ad64e3869dcc' \
   -H 'User-Agent: PostmanRuntime/7.19.0' \
   -H 'cache-control: no-cache' \
   -d '{
    "token": "9e9cf68b-****-****-****-dcb7fcaa341e",
    "url": "https://edrv-ocpi-dev.herokuapp.com/ocpi/versions",
    "roles": [{
     "party_id": "EDV",
     "country_code": "NL",
     "role": "EMSP",
     "business_details": {
      "name": "eDRV Technologies B.V."
     }
    }]
   }'
  </code></pre>
  
  <p>I have setup a quick server on heroku as per step 2 in the tutorial. Here is what the versions endpoint code looks like:</p>
  
  <pre><code>app.get("/ocpi/versions", authorize, async (_, res) =&gt; {
      res.send([{
          status_code: 1000,
          data: {
              versions: [{
                  version: "2.2",
                  url: `${PUBLIC_URL}/ocpi/2.2`
              }]
          },
          timestamp: new Date()
      }])
  })
  </code></pre>
  
  <p>Is there something I am missing in the request?</p>