📃: Add BMI calculator

[Aditijainnn]

🔴 Title : BMI calculator
🔴 Aim : A BMI (Body Mass Index) calculator determines a person's body fat based on their weight and height.
🔴 Tech Stack Used : HTML CSS JS

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✅ To be Mentioned while taking the issue :

• Full name : Aditi Jain
• What is your participant role? gssoc ext and hacktoberfest

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Happy Contributing 🚀

All the best. Enjoy your open source journey ahead. 😎

[github-actions]

Thank you for creating this issue! We'll look into it as soon as possible. Your contributions are highly appreciated! 😊

[Avdhesh-Varshney]

#108