curl --location --request POST '/rest/api/3/priorityscheme' \
--header 'Content-Type: application/json' \
--data-raw '{
    "defaultPriorityId": 10001,
    "description": "My priority scheme description",
    "mappings": {
        "in": {
            "10002": 10000,
            "10005": 10001,
            "10006": 10001,
            "10008": 10003
        },
        "out": {}
    },
    "name": "My new priority scheme",
    "priorityIds": [
        10000,
        10001,
        10003
    ],
    "projectIds": [
        10005,
        10006,
        10007
    ]
}'{"id":"10001"}