docs(showcase): add emojiblast.dev to showcase

[JoshuaKGoldberg]

Description

Adds https://www.emojiblast.dev per https://github.com/withastro/starlight/blob/main/CONTRIBUTING.md#showcase.

[changeset-bot]

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Latest commit: 997007f

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[astrobot-houston]

Hello! Thank you for opening your first PR to Starlight! ✨

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[delucis]

Woo! Thanks @JoshuaKGoldberg 🎊

Initial Netlify deploy failed randomly, but I reran to confirm everything was OK and it was indeed. Happy to have this added to the showcase.

[JoshuaKGoldberg]

Awesome thanks!