Update webpack requirement from ^5.81.0 to ^5.88.1 in /test-app

Updates the requirements on [webpack](https://github.com/webpack/webpack) to permit the latest version.
- [Release notes](https://github.com/webpack/webpack/releases)
- [Commits](webpack/webpack@v5.81.0...v5.88.1)

---
updated-dependencies:
- dependency-name: webpack
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>

test-app/package.json

@@ -80,7 +80,7 @@
     "stylelint-config-standard": "^33.0.0",
     "stylelint-prettier": "^3.0.0",
     "tracked-built-ins": "^3.1.1",
-    "webpack": "^5.81.0"
+    "webpack": "^5.88.1"
   },
   "engines": {
     "node": "16.* || >= 18"