Releasing MacOS prebuilts will break in June 2024

[vmx]

CircleCI is sunsetting all Intel MacOS machines in 2024. Currently we use such a machine to create universal binaries.

We should switch to an ARM based machine and cross-compile to Intel from there (if that's possible, I don't know much about MacOS).

Update: the sunsetting was postponed till June 2024.

[galargh]

filecoin-ffi/install-filcrypto

Lines 162 to 164 in 62960ca

	# For building on Darwin, we try to use cargo-lipo instead of cargo build.
	# Note that the cross compile works on x86_64 for m1, but doesn't work on m1.
	# For m1, we will build natively if building from source.

suggests that it might not be possible.

Is dropping darwin/amd64 support an option?

Alternatively, let me know if you wanted us to look into setting up self-hosted Apple Intel runners.

[vmx]

A possible fix is at #424.