fix: support responses that assign multiple permission codes to the same group (DEV-3482)

[jnussbaum]

This PR introduces support for this response:

https://api.stage.dasch.swiss/admin/permissions/doap/http%3A%2F%2Frdfh.ch%2Fprojects%2F082D

"hasPermissions": [
    {
        "additionalInformation": "http://www.knora.org/ontology/knora-admin#ProjectAdmin",
        "name": "CR",
        "permissionCode": 8
    },
    {
        "additionalInformation": "http://www.knora.org/ontology/knora-admin#ProjectAdmin",
        "name": "RV",
        "permissionCode": 1
    },
    {
        "additionalInformation": "http://www.knora.org/ontology/knora-admin#ProjectAdmin",
        "name": "M",
        "permissionCode": 6
    },
    {
        "additionalInformation": "http://www.knora.org/ontology/knora-admin#ProjectAdmin",
        "name": "V",
        "permissionCode": 2
    },
    {
        "additionalInformation": "http://www.knora.org/ontology/knora-admin#ProjectAdmin",
        "name": "D",
        "permissionCode": 7
    }
]

Previously, this made the constructor of PermissionScope crash, because the validation says that the same group can only belong to one permission code. In the above example: ProjectAdmin belongs to CR only, because all other permission codes are already covered by CR.

[BalduinLandolt]

If it works, it works. But see my question/suggestion regarding simplifying the deduplication logic.

[linear]

DEV-3482 permissions scripts: handle admin route responses that assign multiple permission codes to the same group

--> check with backend if this behaviour of DSP-API is intended or a bug