gh-153313: Run Emscripten PyRepl test in CI

To avoid having to rely on the buildbot for PyRepl test

Author: hoodmane

.github/workflows/reusable-emscripten.yml

@@ -77,3 +77,5 @@ jobs:
       run: python3 Platforms/emscripten pythoninfo-host
     - name: "Test"
       run: python3 Platforms/emscripten run --test
+    - name: "Test Repl"
+      run: Platforms/emscripten/browser_test/run_test.sh