feat: move default musllinux build to musllinux_1_2

[mayeut]

Statistics for musl (mostly Alpine but also some OpenWRT)

BigQuery sql query:

SELECT
  details.distro.name as distro_name,
  details.distro.version as distro_version,
  details.distro.libc.lib as libc_name,
  details.distro.libc.version as libc_version,
  COUNT(*) as download_count,
FROM `bigquery-public-data.pypi.file_downloads`
WHERE timestamp BETWEEN TIMESTAMP_ADD(CURRENT_TIMESTAMP(), INTERVAL -6 DAY) AND TIMESTAMP_ADD(CURRENT_TIMESTAMP(), INTERVAL -1 DAY)
  AND details.installer.name = "pip"
  AND details.system.name = "Linux"
  AND file.filename LIKE "%musllinux%"
  AND (details.distro.libc.lib IS NULL OR details.distro.libc.lib != "glibc")
GROUP BY
  distro_name, distro_version, libc_name, libc_version
ORDER BY
  download_count DESC
LIMIT 100

Once reduced, this gives:

version	percentage
musllinux_1_2	97.5 %
musllinux_1_1	2.5 %

If we omit the filter on musllinux wheel downloads, this gives:

version	percentage
musllinux_1_2	90.5 %
musllinux_1_1	9.5 %

It's worth noting that musl libc 1.1 is EOL and Alpine Linux 3.12 also (support ended 2 years ago, 01 May 2022)

[henryiii]

I'd like to add config examples too, I can do it or you. At https://cibuildwheel.pypa.io/en/stable/options/#examples_12.

[radarhere]

Be aware there's a typo at https://github.com/pypa/cibuildwheel/releases/tag/v2.18.0

Musllinux now defaults to musllinux_1_2. You can set the older manylinux_1_1 via config if needed. (#1817)

I expect it should say 'the older musllinux_1_1'

[henryiii]

Thanks! Fixed in the GH release and docs fix in #1823.