feat: added expiry input on create url

[ivinayakg]

closes #32

Brief

• Added expiry picker on the create shorte URL form.
• Add the ability to see the shorte URL on the success notification.

Demo

[netlify[bot]]

✅ Deploy Preview for url-shortner-golang ready!

Name	Link
🔨 Latest commit	05b957c6e90af870f494497ac90b20e378d8da67
🔍 Latest deploy log	https://app.netlify.com/sites/url-shortner-golang/deploys/65bfe196803a940008c71d3a
😎 Deploy Preview	https://deploy-preview-33--url-shortner-golang.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.