Remove reference to alpine linux from readme

[bdraco]

We provide musllinux wheels now so the readme no longer made sense

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.56%. Comparing base (79d53eb) to head (1eabcc9).
Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1172   +/-   ##
=======================================
  Coverage   95.56%   95.56%           
=======================================
  Files          30       30           
  Lines        4917     4917           
  Branches      446      446           
=======================================
  Hits         4699     4699           
  Misses        192      192           
  Partials       26       26           

Flag	Coverage Δ
CI-GHA	95.52% <ø> (ø)
MyPy	42.13% <ø> (ø)
OS-Linux	99.41% <ø> (ø)
OS-Windows	99.50% <ø> (ø)
OS-macOS	99.13% <ø> (ø)
Py-3.10.11	99.03% <ø> (ø)
Py-3.10.15	99.26% <ø> (ø)
Py-3.11.10	99.26% <ø> (ø)
Py-3.11.9	99.03% <ø> (ø)
Py-3.12.6	99.26% <ø> (ø)
Py-3.13.0-rc.3	99.26% <ø> (ø)
Py-3.8.10	98.98% <ø> (ø)
Py-3.8.18	99.20% <ø> (ø)
Py-3.9.13	98.98% <ø> (ø)
Py-3.9.20	99.20% <ø> (ø)
Py-pypy7.3.11	99.26% <ø> (ø)
Py-pypy7.3.16	99.26% <ø> (ø)
Py-pypy7.3.17	99.29% <ø> (ø)
VM-macos-latest	99.13% <ø> (ø)
VM-ubuntu-latest	99.41% <ø> (ø)
VM-windows-latest	99.50% <ø> (ø)
pytest	99.41% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.