Enable macos CI (#5)

diff --git a/.github/workflows/dotnet.yml b/.github/workflows/dotnet.yml
index 72644de..de4c675 100644
--- a/.github/workflows/dotnet.yml
+++ b/.github/workflows/dotnet.yml
@@ -12,7 +12,7 @@
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ ubuntu-latest, windows-latest ]
+        os: [ ubuntu-latest, windows-latest, macos-latest ]
 
     steps:
     - uses: actions/checkout@v4