Bump react-dropzone from 11.2.0 to 11.2.4 in /packages/webapp

Bumps [react-dropzone](https://github.com/react-dropzone/react-dropzone) from 11.2.0 to 11.2.4.
- [Release notes](https://github.com/react-dropzone/react-dropzone/releases)
- [Commits](https://github.com/react-dropzone/react-dropzone/compare/v11.2.0...v11.2.4)

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

packages/webapp/package.json

@@ -27,7 +27,7 @@
     "react": "16.14.0",
     "react-countup": "4.3.3",
     "react-dom": "16.14.0",
-    "react-dropzone": "11.2.0",
+    "react-dropzone": "11.2.4",
     "react-helmet": "6.1.0",
     "react-mailchimp-form": "1.0.2",
     "react-mailchimp-subscribe": "2.1.0",