How analytics labels can be added to a message?

[dm-aq]

Hi!
How can I add analytics labels for a android push message?
https://firebase.google.com/docs/cloud-messaging/understand-delivery?hl=en&platform=web#adding-analytics-labels-to-messages

[kornrunner]

Duplicate of #444 ?

[appleboy]

Label associated with the message's analytics data.

{
  "notifications": [
    {
      "tokens": ["token_a", "token_b"],
      "platform": 2,
      "message": "Hello World Android!",
      "title": "You got message",
      "fcm_options": {
        "analytics_label": "example"
      }
    }
  ]
}