Trim wheel builds (#320)

* Skip 32-bit wheel builds

Have not been doing testing for 32-bit or supported it for some time. So
drop 32-bit builds from wheels.

* Drop musl builds

This is a bit of an edge case that we are not otherwise testing on. So
skip these builds to lighten the build matrix.

* Drop s390x builds

This is also a bit of an edge case architecture wise. Also we are not
doing any other testing there. So drop it.

Author: jakirkham

.github/workflows/wheel.yaml

@@ -13,7 +13,7 @@ jobs:
     env:
       CIBW_TEST_COMMAND: pytest --pyargs numcodecs
       CIBW_TEST_REQUIRES: pytest
-      CIBW_SKIP: "pp* cp36-*"
+      CIBW_SKIP: "pp* cp36-* *-musllinux_* *win32 *_i686 *_s390x"
       CIBW_ENVIRONMENT: "DISABLE_NUMCODECS_AVX2=1"
       CIBW_ENVIRONMENT_MACOS: 'MACOSX_DEPLOYMENT_TARGET=10.9 DISABLE_NUMCODECS_AVX2=1 CFLAGS="$CFLAGS -Wno-implicit-function-declaration"'