Admin user tries to change his/her own role gives 500 status code

[grgprarup]

Describe the bug

When an Admin user tries to change his/her own role gives a 500 status code, with a response body containing the message 403 Forbidden.

Steps to reproduce

Steps to reproduce the behavior:

1. Create user1
2. Grant role Admin to user1
3. Change user1 role to newRole

Endpoints:

POST: /graph/v1.0/users/user-id/appRoleAssignments/

curl -kv -XPOST -uuser1:1234 https://host.docker.internal:9200/graph/v1.0/users/37130879-7646-44be-9e6c-4ea67c2b7c50/appRoleAssignments \
-H 'Content-Type: application/json' \
-d '{"appRoleId": "2aadd357-682c-406b-8874-293091995fdd","principalId": "37130879-7646-44be-9e6c-4ea67c2b7c50","principalType": "User","resourceDisplayName": "ownCloud Infinite Scale","resourceId": "some-graph-app-id"}'

Expected behavior

HTTP/1.1 403 Forbidden

Actual behavior

HTTP/1.1 500 Internal Server Error

{
    "error": {
        "code": "generalException",
        "innererror": {
            "date": "2023-04-12T11:18:35Z",
            "request-id": "c612df5afef9/cBddd5avYf-014460"
        },
        "message": "{\"id\":\"ocis-settings\",\"code\":403,\"detail\":\"Changing own role assignment forbidden\",\"status\":\"Forbidden\"}"
    }
}

[micbar]

We should fix the error code during the test writing.

[ScharfViktor]

PR #6030 is blocked due to problems: #6037 #6035

status code 500, but response message "{\"id\":\"ocis-settings\",\"code\":403,\"detail\":\"Changing own role assignment forbidden\",\"status\":\"Forbidden\"}"