Build macOS wheels and integration tests

[jamesbornholt]

This is pretty simple, mostly just adding macos-13 (x86) and macos-14 (arm64) runners to the matrix. We also need to explicitly disable MPS for PyTorch to run correctly on the GHA runners which don't have access to that hardware.

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dnanuti@: Build on macos runners had occasionally a flaky behaviour, as actions/setup-python requires /Users/runner/hostedtoolcache to exist to work properly with macosx due to fixed shared library path.
Additionally, pipx was not always properly configured, depending on the runner image, encountered this on macos-14 arm64 runners too (example run).

Also worth mentioning:

Warning: While cibuildwheel can build CPython 3.8 universal2/arm64 wheels, we cannot test the arm64 part of them, even when running on an Apple Silicon machine. This is because we use the x86_64 installer of CPython 3.8. See the discussion in pypa/cibuildwheel#1169 for the details. To silence this warning, set CIBW_TEST_SKIP: "cp38-macosx_*:arm64".

This applies just for the build for 3.8 macosx arm64 and had the same behaviour with the initial changes.

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By submitting this pull request, I confirm that my contribution is made under the terms of BSD 3-Clause License and I agree to the terms of the LICENSE.

[dnanuti]

Why have we changed this?
Should we update the other workflows too: https://github.com/search?q=repo%3Aawslabs%2Fs3-connector-for-pytorch%20actions-rs%2Ftoolchain%40v1&type=code?

[muddyfish]

Are these which lines still wanted?

[dnanuti]

I used them for debugging, but left them on purpose, as they helped to understand the problem, and I am expecting changes for pip setup in the upcoming runner updates.