Added new game "Harmony mixer"

[sidharth2829]

PR Description 📜

Added Game "Harmony Mixer"
Fixes #4295

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Mark the task you have completed ✅

• [ x] I follow CONTRIBUTING GUIDELINE & CODE OF CONDUCT of this project.
• [ x] I have performed a self-review of my own code or work.
• [ x] I have commented my code, particularly in hard-to-understand areas.
• [ x] My changes generates no new warnings.
• [x ] I have followed proper naming convention showed in CONTRIBUTING GUIDELINE
• [x ] I have added screenshot for website preview in assets/images
• [ x] I have added entries for my game in main README.md
• [ x] I have added README.md in my folder
• I have added working video of the game in README.md (optional)
• [ x] I have specified the respective issue number for which I have requested the new game.

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Add your screenshots(Optional) 📸

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Thank you soo much for contributing to our repository 💗

[kunjgit]

Thank you @sidharth2829 ,for creating the PR and contributing to our GameZone 💗
Review team will review the PR and will reach out to you soon! 😇
Make sure that you have marked all the tasks that you are done with ✅.
Thank you for your patience! 😀

[sidharth2829]

@kunjgit , please review my game.

[sidharth2829]

@ishita-43, please can you review my PR.

[kunjgit]

Thank you @sidharth2829 , for your valuable time and contribution in our GameZone 💗.
It’s our GameZone, so Let’s build this GameZone altogether !!🤝
Hoping to see you soon with another PR again 😇
Wishing you all the best for your journey into Open Source🚀

[kunjgit]

Hello @sidharth2829,
You need to make the following changes:

• Please create a new folder inside the "Games" folder.
• Please add a README.md file inside the newly created folder.
• Please modify the main README.md file.
• Please add an image to the assets/images directory.

Hoping that you will make those changes soon 🚀