Update test_build.yml

Author: briantoby

.github/workflows/test_build.yml

@@ -13,7 +13,17 @@ jobs:
   build:       # Build web pages
     runs-on: ubuntu-latest
     steps:
-    
+      - name: sed test
+        run: |
+          mkdir test
+          cat "<figure>" > test.txt
+          echo "before"
+          cat test.txt
+          man sed
+          echo "after"
+          cat test.txt
+          exit
+
       - name: Install pandoc
         uses: pandoc/actions/setup@v1