Bump glob-parent and webpack-dev-server

Bumps [glob-parent](https://github.com/gulpjs/glob-parent) to 5.1.2 and updates ancestor dependency [webpack-dev-server](https://github.com/webpack/webpack-dev-server). These dependencies need to be updated together.


Updates `glob-parent` from 3.1.0 to 5.1.2
- [Release notes](https://github.com/gulpjs/glob-parent/releases)
- [Changelog](https://github.com/gulpjs/glob-parent/blob/main/CHANGELOG.md)
- [Commits](https://github.com/gulpjs/glob-parent/compare/v3.1.0...v5.1.2)

Updates `webpack-dev-server` from 3.11.3 to 4.11.1
- [Release notes](https://github.com/webpack/webpack-dev-server/releases)
- [Changelog](https://github.com/webpack/webpack-dev-server/blob/master/CHANGELOG.md)
- [Commits](https://github.com/webpack/webpack-dev-server/compare/v3.11.3...v4.11.1)

---
updated-dependencies:
- dependency-name: glob-parent
  dependency-type: indirect
- dependency-name: webpack-dev-server
  dependency-type: direct:development
...

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

package.json

@@ -126,7 +126,7 @@
     "webpack": "4.38.0",
     "webpack-cli": "^3.3.12",
     "webpack-dev-middleware": "^3.7.3",
-    "webpack-dev-server": "^3.11.3",
+    "webpack-dev-server": "^4.11.1",
     "webpack-manifest-plugin": "^2.2.0",
     "webpack-unassert-loader": "^1.2.0"
   },