langtour: revert to 0.2.0-rc6 (#534)

This breaks npm publish :(

Author: jgonet

language-tour/package.json

@@ -18,7 +18,7 @@
     "@mdx-js/react": "^3.1.0",
     "@mdx-js/rollup": "^3.1.0",
     "@sentry/react": "^10.17.0",
-    "@swmansion/popcorn": "^0.2.0",
+    "@swmansion/popcorn": "^0.2.0-rc.6",
     "@tailwindcss/vite": "^4.1.11",
     "@types/xxhashjs": "^0.2.4",
     "@uiw/codemirror-theme-solarized": "^4.24.2",