sage

487a02f1 - sagemath-standard: don't require Cython to create sdist

sagemath-standard: don't require Cython to create sdist The implementation of sage.misc.package_dir.read_distributions uses the function `Cython.Utils.open_source_file()` to open a file instead of `io.open()`. This function was introduced in #29701 (b582789). The only difference between `open_source_file()` and `io.open()` is that the former will open the file as binary to check the encoding. But all our files should be utf-8 so we don't need this trick.