curl --request POST \
  --url https://api.member.dev/api/v1/portal/hubs/{hub_id}/me/avatar \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/vnd.api+json' \
  --data '
{
  "data": {
    "attributes": {
      "mime_type": "<string>",
      "size_bytes": 123
    },
    "type": "<string>"
  }
}
'

{
  "detail": [
    {
      "loc": [
        "<string>"
      ],
      "msg": "<string>",
      "type": "<string>",
      "ctx": {},
      "input": "<unknown>"
    }
  ]
}