Add social media preview img

[machikoyasuda]

closes #138

• LinkedIn Post Inspector: https://www.linkedin.com/post-inspector/inspect/https:%2F%2Fdeploy-preview-148--compilerla.netlify.app%2F
• Slack: Send yourself a message with the link

[netlify[bot]]

✅ Deploy Preview for compilerla ready!

Name	Link
🔨 Latest commit	eddcec27192c300b9afbed2fe0f84704131ecc4f
🔍 Latest deploy log	https://app.netlify.com/sites/compilerla/deploys/6541749299c3010008535582
😎 Deploy Preview	https://deploy-preview-148--compilerla.netlify.app
📱 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.

[machikoyasuda]

@thekaveman @angela-tran Last small PR review for blog, and then we're done!