Start Xvfb before running tests.

Chromium requires a virtual display in headless environments.

.github/workflows/build-and-deploy.yml

@@ -242,6 +242,9 @@ jobs:
         docker compose exec -T web /bin/sh -c 'bundle config --local disable_exec_load true'
         docker compose exec -T web /bin/sh -c 'apk add --no-cache chromium chromium-chromedriver xvfb xauth'
         docker compose exec -T web /bin/sh -c "echo 'Checking if chromedriver is installed...'; which chromium; which chromedriver; ls -l /usr/bin/chromium; ls -l /usr/bin/chromedriver; chromium --version; chromedriver --version"
+        # Ensure that xvfb is set up to allow GUI-based apps like Chromium to run headlessly
+        docker compose exec -T web /bin/sh -c 'Xvfb :99 -ac &'
+        docker compose exec -T web /bin/sh -c 'export DISPLAY=:99'
         docker compose exec -T web /bin/sh -c 'bundle exec rake parallel:setup'
 
     - name: ${{ matrix.tests }} tests