Microsoft MessageCard:如何指定邮件优先级

{
  "@type": "MessageCard",
  "themeColor": "0078D7",
  "title": "邮件优先级",
  "text": "这封邮件的优先级是高。",
  "potentialAction": [
    {
      "@type": "ActionCard",
      "name": "设为高优先级",
      "actions": [
        {
          "@type": "HttpPOST",
          "name": "设为高优先级",
          "target": "https://example.com/set-priority?priority=high"
        }
      ]
    },
    {
      "@type": "ActionCard",
      "name": "设为普通优先级",
      "actions": [
        {
          "@type": "HttpPOST",
          "name": "设为普通优先级",
          "target": "https://example.com/set-priority?priority=normal"
        }
      ]
    },
    {
      "@type": "ActionCard",
      "name": "设为低优先级",
      "actions": [
        {
          "@type": "HttpPOST",
          "name": "设为低优先级",
          "target": "https://example.com/set-priority?priority=low"
        }
      ]
    }
  ]
}