CI: test all available OS in CI

Author: oscarbenjamin

.github/workflows/buildwheel.yml

@@ -83,7 +83,17 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-24.04, ubuntu-24.04-arm, windows-2019, macos-13, macos-14]
+        os: [
+          ubuntu-22.04,
+          ubuntu-24.04,
+          ubuntu-24.04-arm,
+          windows-2019,
+          windows-2022,
+          windows-2025,
+          macos-13,
+          macos-14,
+          macos-15,
+        ]
         # This list to be kept in sync with python-requires in pyproject.toml.
         python-version: ['3.11', '3.12', '3.13', '3.13t', 'pypy3.11']