chore: Add Dependabot configuration file

[yagizhanNY]

💡 What is the current behavior?

We have to trace dependencies'' versions manually.

GitHub Issue Number: #51

🆕 What is the new behavior?

Now, we can set CRON job for dependabot to trace our dependency versions automatically.

🏁 Checklist

A pull request can only be merged if all of these conditions are met (where applicable):

• [ ] 🦮 Accessibility (a11y) features were implemented
• [ ] 🗺️ Internationalization (i18n) - no hard coded strings
• [ ] 📲 Responsiveness - components handle viewport changes and content overflow gracefully
• [ ] 📄 Documentation was reviewed/updated
• [x] 🧪 Unit tests were added/updated and pass (dotnet test)
• [x] 🏗️ Successful compilation (dotnet build, changes pushed)

👨‍💻 Help & support