fix: superset-frontend/temporary_superset_ui/superset-ui-plugins-deck…

…gl/packages/superset-ui-plugins-demo/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-WEBPACKDEVMIDDLEWARE-6476555

superset-frontend/temporary_superset_ui/superset-ui-plugins-deckgl/packages/superset-ui-plugins-demo/package.json

@@ -36,7 +36,7 @@
     "@storybook/addon-knobs": "^5.0.9",
     "@storybook/addon-links": "^5.0.9",
     "@storybook/addons": "^5.0.9",
-    "@storybook/react": "^5.0.9",
+    "@storybook/react": "^6.2.0",
     "@types/react": "^16.9.49",
     "@types/storybook__react": "3.0.7",
     "bootstrap": "^4.3.1",