fix: nunjucks nested component syntax typo

[AurorahHarmony]

The documentation showed the incorrect syntax for using nested components. I have fixed this.

[netlify[bot]]

✅ Deploy Preview for lumeland ready!

Name	Link
🔨 Latest commit	4c680df9139fc6038396fa84ac5c761518d8c183
🔍 Latest deploy log	https://app.netlify.com/sites/lumeland/deploys/6555e5f832f4fd0008d031c4
😎 Deploy Preview	https://deploy-preview-89--lumeland.netlify.app/docs/core/components
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[oscarotero]

Thank you!