Rectified issues in comments for NotificationMessagePayload

[VPanjeta]

The comments regarding the NotificationMessagePayload were not correct. They were placed with different options.
The comment related to tag was attached to sound and tag did not have any comment attached.

Had an issue understanding the payload the first time I opened the installed directory to go through the payload of sendToDevice

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[VPanjeta]

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[lahirumaramba]

Thank you @VPanjeta !

Looks like this was previously addressed in #820, but was broken by #751 right after.

[lahirumaramba]

/**
* The sound to play when the device receives the notification. Supports
* "default" or the filename of a sound resource bundled in the app. Sound files
* must reside in `/res/raw/`.
* * **Platforms:** Android
*/

I think the docs from #820 might be more suitable here. I will leave @egilmorez to confirm.

[VPanjeta]

Ok since it is already present in #820 . Closing this for now.

[lahirumaramba]

It was addressed in #820 but was broken again in #751. Therefore we could still use this PR.
Please update the comments (docs) to the suggested text in my review and we should be good to merge this. Thanks!

[VPanjeta]

@lahirumaramba Made the changes as expected. Do let me know if anything else is needed.

[egilmorez]

Since we are using articles everywhere else (instead of the extra-concise style that omits them), we should probably use them here too:

"The sound to be played when the device receives a notification. Supports
* * "default" for the default notification sound of the device"

[egilmorez]

Thanks for sending! LG with one nit regarding articles.

[VPanjeta]

@egilmorez Sorry for having some semantic/grammatical errors. English isn't my native language. Pushed a commit after adding articles to the comments. Hopefully that fixes your concerns.
Do let me know if I'm still missing something.

[lahirumaramba]

Thank you @VPanjeta !
LGTM!

[egilmorez]

Thanks!