Add missing instanceName to the MssqlConnectionNode type

[Imunal]

🔗 Linked issue

https://github.com/adonisjs/lucid/issues/916

❓ Type of change

• [ ] 🐞 Bug fix (a non-breaking change that fixes an issue)
• [ ] 👌 Enhancement (improving an existing functionality like performance)
• [x] ✨ New feature (a non-breaking change that adds functionality)
• [ ] ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Add missing instanceName option in the MssqlConnectionNode type, which is required to setup if MSSQL is running using instance.

📝 Checklist

• [x] I have linked an issue or discussion.
• [ ] I have updated the documentation accordingly.

[thetutlage]

Thanks 👍