IPv6 fields do not validate in pedantic mode

[edeca]

In pedantic mode, IPv6 entries are not correctly validated. These are listed with support since version 6.1.

Minimum PoC:

{
  "reports": [
    {
      "link": "https://nccgroup.com/blog/",
      "id": "50d858e0985ecc7f60418aaf0cc5ab587f42c2570a884095a9e8ccacd0f6545c",
      "score": 50,
      "title": "IOCs from NCC Group APT123 blog post",
      "iocs": {
        "ipv6": [
          "2001:DB8::1"
        ]
      }
    }
  ],
  "feedinfo": {
    "summary": "This is my feed",
    "tech_data": "Some technical data",
    "provider_url": "https://nccgroup.com/",
    "display_name": "NCC Group collated feed",
    "name": "nccgroup"
  }
}

Test case:

-> % python validate_feed.py --pedantic -f temp.json
-> Validated that file exists and is readable
-> Validated that feed file is valid JSON
-> Unable to validate that the file is a valid CB feed
-> Details:

Report IOCs section contains extra keys: set([u'ipv6'])

It seems likely the function iter_iocs needs to be updated.