Adjust Kubecon promo banner to latest changes

[rlamana]

The promo will now appear in the "nav bar", next to the new admin button:

[github-actions[bot]]

Your preview environment pr-93-cindylopez has been deployed.

Preview environment endpoints are available at:

• https://movies-pr-93-cindylopez.demo.okteto.dev/rent
• https://movies-pr-93-cindylopez.demo.okteto.dev/users
• https://movies-pr-93-cindylopez.demo.okteto.dev/rentals
• https://movies-pr-93-cindylopez.demo.okteto.dev/catalog
• https://movies-pr-93-cindylopez.demo.okteto.dev
• https://movies-pr-93-cindylopez.demo.okteto.dev/admin