Inconsistent rendering of missing relationship information

[kd-ods]

Describe the bug

According to the spec, the default rendering of an edge is a black dotted line.

This is what happens when the following code is used:

[...]
    "recordType": "relationship",
    "recordDetails": {
      "subject": "c359f58d2977",
      "interestedParty": "10478c6cf6de"
    }
[...]

The above is correct. The next two code snippets are informationally equivalent but are (incorrectly) rendered differently:

[...]
    "recordType": "relationship",
    "recordDetails": {
      "subject": "c359f58d2977",
      "interestedParty": "10478c6cf6de",
      "interests": []
    }
[...]

And:

[...]
    "recordType": "relationship",
    "recordDetails": {
      "subject": "c359f58d2977",
      "interestedParty": "10478c6cf6de",
      "interests": [
        {}
      ]
    }
[...]

To Reproduce
Steps to reproduce the behaviour:

1. Paste the following into the visualiser and edit it.

[
  {
    "statementId": "1dc0e987-5c57-4a1c-b3ad-61353b66a9b7",
    "declarationSubject": "c359f58d2977",
    "statementDate": "2020-03-04",
    "publicationDetails": {
      "bodsVersion": "0.4"
    },
    "recordId": "c359f58d2977",
    "recordStatus": "new",
    "recordType": "entity",
    "recordDetails": {
      "name": "Profitech Ltd",
      "foundingDate": "2019-09-03"
    }
  },
  {
    "statementId": "019a93f1-e470-42e9-957b-03559861b2e2",
    "declarationSubject": "c359f58d2977",
    "statementDate": "2020-03-04",
    "publicationDetails": {
      "bodsVersion": "0.4"
    },
    "recordId": "10478c6cf6de",
    "recordStatus": "new",
    "recordType": "person",
    "recordDetails": {
      "personType": "knownPerson",
      "names": [
        {
          "type": "legal",
          "fullName": "Jennifer Hewitson-Smith",
          "givenName": "Jennifer",
          "familyName": "Hewitson-Smith"
        }
      ]
    }
  },
  {
    "statementId": "fbfd0547-d0c6-4a00-b559-5c5e91c34f5c",
    "declarationSubject": "c359f58d2977",
    "statementDate": "2020-03-04",
    "publicationDetails": {
      "bodsVersion": "0.4"
    },
    "recordId": "93b53022ae6a",
    "recordStatus": "new",
    "recordType": "relationship",
    "recordDetails": {
      "subject": "c359f58d2977",
      "interestedParty": "10478c6cf6de",
      "interests": [
        {}
      ]
    }
  }
]

Expected behaviour

In all three cases, a black dotted line (as in the first screenshot) should be rendered.

Additional context
Add any other context about the problem here.