Add type "SubjectHeading" as fallback for RSWK-subjets that have no GND Id.

[TobiasNx]

It seems that the non GND RSWK subjects used to be typed "SubjectHeading" in ALEPH Transformation as fallback. (https://github.com/hbz/lobid-resources/blob/7f982c13a25f9d6a4ef1a2c81a3749cf1cdaed36/src/main/resources/morph-hbz01-to-lobid.xml#L579-L600)

see example: Aleph:http://aleph.lobid.org/resources/HT006813395.json

 "subject": [
    {
      "type": [
        "ComplexSubject"
      ],
      "componentList": [
        {
          "id": "https://d-nb.info/gnd/4009104-1",
          "type": [
            "SubjectHeading"
          ],
          "source": {
            "id": "https://d-nb.info/gnd/7749153-1",
            "label": "Gemeinsame Normdatei (GND)"
          },
          "label": "Burg",
          "gndIdentifier": "4009104-1"
        },
        {
          "type": [
            "SubjectHeading"
          ],
          "label": "Geschichte"
        }
      ],
      "label": "Burg | Geschichte"
    }
  ],

ALMA: http://lobid.org/resources/990026405480206441.json

 "subject": [
    {
      "type": [
        "ComplexSubject"
      ],
      "label": "Burg | Geschichte",
      "componentList": [
        {
          "type": [
            "SubjectHeading"
          ],
          "label": "Burg",
          "source": {
            "label": "Gemeinsame Normdatei (GND)",
            "id": "https://d-nb.info/gnd/7749153-1"
          },
          "id": "https://d-nb.info/gnd/4009104-1",
          "gndIdentifier": "4009104-1",
          "altLabel": [
            "Burgen"
          ]
        },
        {
          "label": "Geschichte"
        }
      ]
    }
  ]

See: https://github.com/hbz/lobid-resources/pull/2029#issuecomment-2154386682

[dr0i]

Check next Monday.