AArch64 container image

[MrAnno]

This PR introduces aarch64 images. I'm leaving it in draft status until the arm64 GitHub Actions runners are publicly available.

https://github.blog/news-insights/product-news/arm64-on-github-actions-powering-faster-more-efficient-build-systems/

We expect to begin offering Arm runners for open source projects by the end of the year.

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The images won’t double in number again because multi-arch manifests are used, so it looks like this on the user side:

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4 image builders, merged into 2 images (alpine, debian) using multi-arch manifests:

The motivation is dual again:

• ARM platforms are getting more widespread, especially in cloud environments (for example, AWS Graviton), offering a more cost-effective alternative to x86-64.
• the image would help create local test and dev environments (for example, Kubernetes deployments) on Apple silicon laptops.

Special thanks to @pepov

[MrAnno]

ARM runners are now available for open-source projects.

https://github.blog/changelog/2025-01-16-linux-arm64-hosted-runners-now-available-for-free-in-public-repositories-public-preview/