Bump shiki from 3.8.1 to 3.9.1 in /landing-page

Bumps [shiki](https://github.com/shikijs/shiki/tree/HEAD/packages/shiki) from 3.8.1 to 3.9.1.
- [Release notes](https://github.com/shikijs/shiki/releases)
- [Commits](https://github.com/shikijs/shiki/commits/v3.9.1/packages/shiki)

---
updated-dependencies:
- dependency-name: shiki
  dependency-version: 3.9.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

landing-page/package-lock.json

@@ -30,7 +30,7 @@
     "remark": "^15.0.1",
     "remark-gfm": "^4.0.1",
     "remark-html": "^16.0.1",
-    "shiki": "^3.8.1",
+    "shiki": "^3.9.1",
     "tailwind-merge": "^3.3.1"
   },
   "devDependencies": {