chore(deps-dev): bump newspack-scripts from 5.1.1 to 5.2.1

Bumps [newspack-scripts](https://github.com/Automattic/newspack-scripts) from 5.1.1 to 5.2.1.
- [Release notes](https://github.com/Automattic/newspack-scripts/releases)
- [Commits](Automattic/newspack-scripts@v5.1.1...v5.2.1)

---
updated-dependencies:
- dependency-name: newspack-scripts
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

package.json

@@ -18,6 +18,6 @@
     "url": "https://github.com/Automattic/super-cool-ad-inserter-plugin/issues"
   },
   "devDependencies": {
-    "newspack-scripts": "^5.1.1"
+    "newspack-scripts": "^5.2.1"
   }
 }