How to include image in README.md
The most elegant way I found is to follow this post: https://stackoverflow.com/a/42677655. At specific version, the image referred to is a fixed link.
To save Github build resources
The most expensive build action is for macOS: Your 2,420.00 included minutes used consists of 342.00 Ubuntu 2-core minutes, 328.00 Windows 2-core minutes, and 1,750.00 macOS 3-core minutes.
Since I'm using Mac for development already, I can run the following command to build it locally.
rustup target add x86_64-apple-darwin # only once
CIBW_BUILD=cp38-* MACOSX_DEPLOYMENT_TARGET=10.12 CIBW_ARCHS_MACOS=universal2 python -m cibuildwheel --output-dir target