ci: check on all OS

Author: theoludwig

.github/workflows/ci.yml

@@ -8,7 +8,10 @@ on:
 
 jobs:
   build_and_lint:
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
     steps:
       - uses: actions/checkout@v4