Arm builds

[sdvillal]

Checklist

• Used a personal fork of the feedstock to propose changes
• Bumped the build number (if the version is unchanged)
• Reset the build number to 0 (if the version changed)
• Re-rendered with the latest conda-smithy (Use the phrase @conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• Ensured the license file is being packaged.

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This PR:

• activates linux-aarch64
• activates osx-arm64
• sets pixi as build tool

We might need to bring the patches in the nix package as specified in this issue: TimoLassmann/kalign#65

[conda-forge-admin]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe/recipe.yaml) and found it was in an excellent condition.

[sdvillal]

It seems skbuild is not playing well with cross-compilation in osx