feat: Docker image arm support

[abbudao]

Draft for arm support for bloom.

Proposed changes

• Support docker images for arm64 by leveraging buildx multi-platform images.
• Changed optimize for speed instead of size. This will lead to a binary 800kb larger but with a possibly optimized binary.
• Use codegen-units=1 for slower compilations but better results
• Stop using musl to use glibc. I had problems with performance issues and weird DNS behaviors using musl in the past. As you probably know, musl is intended to be a more straightforward implementation and is less optimized than glibc. For this change work, we need to switch from scratch to distroless, increasing the final image size from 5 MB to 28MB, which I believe is still tiny.