Switch to `juliaup`

I am wondering if this feedstock can switch to a [`juliaup`](https://github.com/JuliaLang/juliaup)-based distribution on conda forge? Here are the reasons for doing so:

1. Apple is completely [switching their computers to Apple silicon](https://en.wikipedia.org/wiki/Mac_transition_to_Apple_silicon), so I think it is important we get osx-arm working.
- However, [Julia does not support cross compilation](https://github.com/JuliaLang/julia/issues/30338), so we can't ever build it on the osx-64 worker, despite the multiple attempts to get it working (https://github.com/conda-forge/julia-feedstock/pull/224, https://github.com/conda-forge/julia-feedstock/pull/252).
- There are no M-series workers available for conda-forge.
2. Windows is not yet integrated https://github.com/conda-forge/julia-feedstock/pull/168, and seems difficult to get working.
3. Significantly lower maintenance burden.

What do you think @mkitti @ngam @staticfloat @stevengj? How hard would it be to switch to juliaup? Are there any attempts at doing so?