Add aarch64 build

[AlexanderWells-diamond]

Draft PR to test CI builds of aarch64

[codecov]

Codecov Report

Merging #122 (0e40396) into master (63995ce) will not change coverage.
The diff coverage is n/a.

❗ Current head 0e40396 differs from pull request most recent head ce88654. Consider uploading reports for the commit ce88654 to get more accurate results

@@ Coverage Diff @@## master #122 +/- ##
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Coverage 87.15% 87.15% =======================================
Files 14 14 Lines 981 981 =======================================
Hits 855 855 Misses 126 126 

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[github-actions]

Unit Test Results

0 files - 15 0 suites - 15 0s ⏱️ - 29m 44s
0 tests - 249 0 ✔️ - 243 0 💤 - 6 0 ❌ ±0 
0 runs - 3 735 0 ✔️ - 3 295 0 💤 - 440 0 ❌ ±0 

Results for commit d7262fd. ± Comparison against base commit 63995ce.

[Araneidae]

Possible good news for the future: https://github.blog/changelog/2023-10-30-accelerate-your-ci-cd-with-arm-based-hosted-runners-in-github-actions/ ?

[AlexanderWells-diamond]

There are now arch64 runners available publicly: https://github.com/actions/partner-runner-images

I made an attempt as part of PR #198 to add these runners, but neither Windows or Ubunutu runners worked easily. Problems included:

• cibuildwheel wouldn't accept the platform as valid (probably as it was using an old version of cibuildwheel)
• Some platforms ran all the way through to the end of the tests, but crashed somewhere in pytest's cleanup.
• Some platforms try to compile numpy! Probably something to do with how we retrieve the wheels.

I'll leave this PR open as a reminder to come back to it eventually...