Update ci.yml

[kimikage]

This adds x86 (32-bit) and aarch64 systems to the test targets.
The test fails on 32-bit systems. (cf. #16)

codecov/codecov-action@v4 requires CODECOV_TOKEN.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.35%. Comparing base (f16eec8) to head (ff6eef2).

❗ Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

@@           Coverage Diff           @@
##           master      #17   +/-   ##
=======================================
  Coverage   99.35%   99.35%           
=======================================
  Files           1        1           
  Lines         468      468           
=======================================
  Hits          465      465           
  Misses          3        3           

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

[GunnarFarneback]

Thanks for also generally updating the CI.