Update GitHub Actions

- Modifies `ipywidgets-bokeh-ci.yml` to include python tests.

Author: perovskite

.github/workflows/ipywidgets-bokeh-ci.yml

@@ -43,13 +43,20 @@ jobs:
         run: |
           npm run build
 
-      - name: Run tests
+      - name: Run JavaScript tests
         if: success() || failure()
         working-directory: ./ipywidgets_bokeh
         shell: bash
         run: |
           npm run test
 
+      - name: Run Playwright & Python tests
+        if: success() || failure()
+        working-directory: ./ipywidgets_bokeh
+        shell: bash
+        run: |
+          pytest
+
       - name: Lint codebase
         if: success() || failure()
         working-directory: ./ipywidgets_bokeh