Run test on multiple machines

Author: inbaltako

.github/workflows/test.yml

@@ -8,7 +8,10 @@ on:
 
 jobs:
   test:
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [macos-latest, ubuntu-latest, windows-latest]
     steps:
     - uses: actions/checkout@v2
     - name: Set up Python
@@ -44,4 +47,4 @@ jobs:
         message_id: ${{ steps.slack.outputs.message_id }}
         channel: github-actions
         status: FAILED
-        color: danger
+        color: danger