[dev app] Add 2 sound files "click.wav" and "bark.wav"

[nan-li]

One Line Summary

Add 2 short sound files to dev app.

Details

Motivation

• This allows testing custom sounds in notifications

Scope

• Dev app resources only
• Added folder Sound containing 2 wav sounds to app
• Credit: https://freesound.org/people/Sadiquecat/sounds/799124 and https://freesound.org/people/abhisheky948/sounds/625497

Testing

Manual testing

Tested sending notification from dashboard using both sounds, and works.

Affected code checklist

• Notifications
  • Display
  • Open
  • Push Processing
  • Confirm Deliveries
• Outcomes
• Sessions
• In-App Messaging
• REST API requests
• Public API changes

Checklist

Overview

• I have filled out all REQUIRED sections above
• PR does one thing
• Any Public API changes are explained in the PR details and conform to existing APIs

Testing

• I have included test coverage for these changes, or explained why they are not needed
• All automated tests pass, or I explained why that is not possible
• I have personally tested this on my device, or explained why that is not possible

Final pass

• Code is as readable as possible.
• I have reviewed this PR myself, ensuring it meets each checklist item

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This change is