Try again to skip pypy builds

.github/workflows/build_cibuildwheel.yml

@@ -33,8 +33,8 @@ jobs:
           CIBW_ARCHS_MACOS: universal2
           CIBW_ENVIRONMENT_MACOS: MACOSX_DEPLOYMENT_TARGET=10.15
           CIBW_BUILD_VERBOSITY_WINDOWS: 2
-          CIBW_SKIP: "*pypy* *cp36*"
+          CIBW_SKIP: "*pypy* *pp* *cp36*"
 
       - uses: actions/upload-artifact@v2
         with:
-          path: ./wheelhouse/*.whl
\ No newline at end of file
+          path: ./wheelhouse/*.whl