Add v17 announcement blog post content

[mattlord]

Description

This PR adds the blog for announcing Vitess 17.

Preview link: https://deploy-preview-1506--vitess.netlify.app/blog/2023-06-27-announcing-vitess-17/

Related Issues

• Part of: https://github.com/vitessio/vitess/issues/13151
• Fixes: https://github.com/vitessio/website/issues/1505

[netlify[bot]]

✅ Deploy Preview for vitess ready!

Name	Link
🔨 Latest commit	172a12dfbbf76fcc096883e06ab77e3d2a1c2c19
🔍 Latest deploy log	https://app.netlify.com/sites/vitess/deploys/649af89afe04100008c9e8f8
😎 Deploy Preview	https://deploy-preview-1506--vitess.netlify.app/blog/2023-06-27-announcing-vitess-17
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

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