Revert "ci: wheel building, why no cython on mac?"

This reverts commit 91749c3.

Author: proycon

.github/workflows/wheels.yml

@@ -38,8 +38,7 @@ jobs:
               ./build-deps.sh
            CIBW_BEFORE_ALL_MACOS: >
               brew tap fbkarsdorp/homebrew-lamachine &&
-              brew install frog &&
-              pip install cython
+              brew install frog
            CIBW_MANYLINUX_X86_64_IMAGE: quay.io/pypa/manylinux2014_x86_64
            CIBW_SKIP: "*-win* *-manylinux_i686 pp*"