add windows compiler

Author: jkotan

.github/workflows/tests.yml

@@ -69,6 +69,7 @@ jobs:
     runs-on: windows-2025    
     steps:
       - uses: actions/checkout@v4
+      - uses: ilammy/msvc-dev-cmd@v1
       - uses: prefix-dev/setup-pixi@v0.9.4
         with:
           pixi-version: v0.62.2