[Messaging] Unable to get messaging to validate APNS payload with apns-push-type header field

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### [REQUIRED] Step 2: Describe your environment

* Operating System version: iOS
* Firebase SDK version: 11.11.0
* Firebase Product: Messaging
* Node.js version: 16.13.1
* NPM version: 8.10.1

### [REQUIRED] Step 3: Describe the problem
I'm attempting to set more particular fields into the messaging send() function, however I continue to get failures as messaging().send() validates the JSON.

#### Steps to reproduce:

What happened? How can we make the problem occur?
Any time I add ```apns-push-type``` I seem to get these failures

This will print Firestore logs to the console.

```
> {"severity":"ERROR","message":"Unhandled error FirebaseMessagingError: Invalid [apns-push-type] set for apns platform\n at Function.fromServerError (/Users/evananger/Developer/blazebite-functions/functions/node_modules/firebase-admin/lib/utils/error.js:254:16)\n at createFirebaseError (/Users/evananger/Developer/blazebite-functions/functions/node_modules/firebase-admin/lib/messaging/messaging-errors-internal.js:35:47)\n at /Users/evananger/Developer/blazebite-functions/functions/node_modules/firebase-admin/lib/messaging/messaging-api-request-internal.js:79:75\n at processTicksAndRejections (node:internal/process/task_queues:96:5)\n at async /Users/evananger/Developer/blazebite-functions/functions/node_modules/firebase-functions/lib/common/providers/https.js:458:26\n at async runFunction (/Users/evananger/.nvm/versions/node/v16.13.1/lib/node_modules/firebase-tools/lib/emulator/functionsEmulatorRuntime.js:506:9)\n at async runHTTPS (/Users/evananger/.nvm/versions/node/v16.13.1/lib/node_modules/firebase-tools/lib/emulator/functionsEmulatorRuntime.js:531:5)\n at async /Users/evananger/.nvm/versions/node/v16.13.1/lib/node_modules/firebase-tools/lib/emulator/functionsEmulatorRuntime.js:694:21 {\n errorInfo: {\n code: 'messaging/invalid-argument',\n message: 'Invalid [apns-push-type] set for apns platform'\n },\n codePrefix: 'messaging'\n}"}
```

#### Relevant Code:

```
function sendOrderReady(token) {
const date = new Date();
return admin.messaging().send({
token,
apns: {
headers: {
'apns-push-type': 'liveactivity',
'apns-priority': '10'
},
payload: {
aps: {
timestamp: date.getTime(),
event: 'update',
'content-state': {
orderCompleteDate: date.toISOString(),
orderReady: true
}

}
}
}
})
}
```