[CI] Move tests on aarch64 linux to GitHub Actions

[giordano]

Let's see how this fares. The idea is to reduce a little bit pressure on the juliaecosystem runners.

[giordano]

Queue is quite long at the moment, we aren't going to gain much for the time being 🥲

[mofeing]

A lot of people might be trying to use it too. Let's give a couple of days and trigger another run then.

[imciner2]

It doesn't have the 64 suffix. So, the long wait time is because it is trying to run a job on a runner that doesn't exist.

[giordano]

🤦

[giordano]

https://github.com/EnzymeAD/Reactant.jl/actions/runs/12820824033/job/35751035540#step:9:778

     CondaPkg Creating environment
             │ /home/runner/.julia/artifacts/528c740035ea96b4091a42660cac663aa0a3f036/bin/micromamba
             │ -r /home/runner/.julia/scratchspaces/0b3b1443-0f03-428d-bdfb-f27f9c1191ea/root
             │ create
             │ -y
             │ -p /tmp/jl_BCzCK3/.CondaPkg/env
             │ --override-channels
             │ --no-channel-priority
             │ libstdcxx-ng[version='>=3.4,<13.0']
             │ python[version='>=3.8,<4',channel='conda-forge',build='*cpython*']
             │ uv[version='>=0.4']
             └ -c conda-forge
info     libmamba ****************** Backtrace Start ******************
debug    libmamba Loading configuration
trace    libmamba Compute configurable 'create_base'
trace    libmamba Compute configurable 'no_env'
trace    libmamba Compute configurable 'no_rc'
trace    libmamba Compute configurable 'rc_files'
trace    libmamba Compute configurable 'root_prefix'
trace    libmamba Get RC files configuration from locations up to HomeDir
trace    libmamba Configuration not found at '/home/runner/.mambarc'
trace    libmamba Configuration not found at '/home/runner/.mamba/mambarc.d'
trace    libmamba Configuration not found at '/home/runner/.mamba/mambarc'
trace    libmamba Configuration not found at '/home/runner/.mamba/.mambarc'
critical libmamba filesystem error: status: Permission denied [/home/runneradmin/.config/mamba/mambarc.d]
info     libmamba ****************** Backtrace End ********************

wut