ci: add e2e test w/ playwright connection

Author: krichprollsch

.github/workflows/e2e-test.yml

@@ -137,3 +137,9 @@ jobs:
           ./lightpanda serve & echo $! > LPD.pid
           node puppeteer/dump.js || exit 1
           kill `cat LPD.pid`
+
+      - name: run playwright connect
+        run: |
+          ./lightpanda serve & echo $! > LPD.pid
+          node playwright/connect.js || exit 1
+          kill `cat LPD.pid`