Changing test workflow to matrix

Author: timheuer

.github/workflows/test-ubuntu.yml renamed to .github/workflows/test-matrix.yml

@@ -7,7 +7,10 @@ on:
 jobs:
   # test action works running from the graph  
   test:
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest]
     steps:
     - name: Checkout
       uses: actions/checkout@v1
@@ -23,5 +26,5 @@ jobs:
     - name: Upload Artifact
       uses: actions/upload-artifact@master
       with:
-        name: 'final-file.txt'
+        name: 'final-file-${{ matrix.os }}.txt'
         path: ${{ steps.write_file.outputs.filePath }}