curl --request PATCH \
  --url https://{server}/api/admin/users/{id}/ \
  --header 'Content-Type: application/json' \
  --cookie sessionid= \
  --data '
{
  "is_active": true,
  "is_system_admin": true
}
'

{
  "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "email": "jsmith@example.com",
  "name": "<string>",
  "is_active": true,
  "is_system_admin": true,
  "organizations": [
    {
      "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
      "name": "<string>"
    }
  ],
  "date_joined": "2023-11-07T05:31:56Z",
  "last_login": "2023-11-07T05:31:56Z",
  "is_last_active_sysadmin": true
}