fix: allow overriding nested variables

[danielroe]

🔗 Linked issue

reverts 686320e

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Returning true allows for overriding nested variables.

📝 Checklist

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

[pi0]

You are right. It stopped working i was trying on a workaround to support NITRO_FOO + NITRO_FOO_BAR and needed this fix but seems more complicated issue.