Add parallel testing demo

Author: chingc

.github/workflows/parallel.yml

@@ -25,13 +25,13 @@ jobs:
           uv tree
 
       - name: Collect tests
-        run: |
-          uv run -- pytest --collect-only --quiet > collected.txt
-          cat collected.txt
+        run: uv run -- pytest --collect-only --quiet | tee collected.txt
 
       - shell: uv run -- python {0}
         run: |
-          print("hello")
+          with open("collected.txt") as lines:
+            for line in lines:
+              print(line.strip())
 
   test:
     name: Test