npm: bump @types/react-dom from 18.2.19 to 18.2.20

Bumps [@types/react-dom](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/react-dom) from 18.2.19 to 18.2.20.
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/react-dom)

---
updated-dependencies:
- dependency-name: "@types/react-dom"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

package.json

@@ -28,7 +28,7 @@
     "@types/koa": "^2.15.0",
     "@types/koa-static": "^4.0.4",
     "@types/react": "^18.2.62",
-    "@types/react-dom": "^18.2.19",
+    "@types/react-dom": "^18.2.20",
     "@types/webpack": "^5.28.5",
     "babel-loader": "^9.1.3",
     "css-loader": "^6.10.0",