use os as key

Massimiliano Pippi · Massimiliano Pippi · commit 6d945d98feea · 2019-08-27T16:02:13.000+02:00
diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
@@ -7,7 +7,7 @@ jobs:
 
     strategy:
       matrix:
-        operating-system: [ubuntu-18.04, windows-2019]
+        os: [ubuntu-18.04, windows-2019]
 
     runs-on: ${{ matrix.operating-system }}
 
