chore: bump alpine to 3.21.0

[aleoli]

Description

This pr bumps the alpine versions

[adamjensenbot]

Hi @aleoli. Thanks for your PR!

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Make sure this PR appears in the liqo changelog, adding one of the following labels:

• kind/breaking: 💥 Breaking Change
• kind/feature: 🚀 New Feature
• kind/bug: 🐛 Bug Fix
• kind/cleanup: 🧹 Code Refactoring
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[aleoli]

/test

[fra98]

/merge