Add pixi package.

[dlorenc]

Fixes:

Related:

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For new package PRs only

• This PR is marked as fixing a pre-existing package request bug
  • Alternatively, the PR is marked as related to a pre-existing package request bug, such as a dependency
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[wolfv]

Wow, this is cool! Thanks @dlorenc. I also like your way of building packages, looks a lot cleaner than current "conda recipes". We are trying to improve things for the conda world with rattler-build (https://github.com/prefix-dev/rattler-build) :)