'Non-unique identifiers' heading count wrong

[odscjames]

From Open-Telecoms-Data/lib-cove-ofds#51 (comment)

Whilst testing I noticed that the failure count in the heading is incorrect:

Some basic test data for posterity:

{
  "networks": [
    {
      "id": "31d17f87-c931-4b69-9341-5e3f1a095000",
      "nodes": [
        {
          "id": "1"
        },
        {
          "id": "1"
        },
        {
          "id": "1"
        }
      ]
    }
  ]
}

[odscjames]

Ready to test on live

[duncandewhurst]

Looks good!