chore(sandbox): upgrade sandbox packages (#444)

Co-authored-by: Upgrade sandbox packages action <>

Author: github-actions[bot]

package-lock.json

@@ -14,7 +14,7 @@
     "@gravity-ui/markdown-editor": "^15.1.0",
     "@gravity-ui/navigation": "^3.6.4",
     "@gravity-ui/page-constructor": "^6.0.0-beta.6",
-    "@gravity-ui/uikit": "^7.20.0",
+    "@gravity-ui/uikit": "^7.21.0",
     "@gravity-ui/uikit-themer": "^1.4.1",
     "@mdx-js/mdx": "^2.3.0",
     "@mdx-js/react": "^2.3.0",