build(deps): bump prismjs from 1.25.0 to 1.27.0 in /demo

Bumps [prismjs](https://github.com/PrismJS/prism) from 1.25.0 to 1.27.0.
- [Release notes](https://github.com/PrismJS/prism/releases)
- [Changelog](https://github.com/PrismJS/prism/blob/master/CHANGELOG.md)
- [Commits](PrismJS/prism@v1.25.0...v1.27.0)

---
updated-dependencies:
- dependency-name: prismjs
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

demo/package-lock.json

@@ -40,7 +40,7 @@
     "materialize-css": "^0.100.2",
     "ngx-markdown": "^13.0.0",
     "prism-themes": "^1.9.0",
-    "prismjs": "^1.25.0",
+    "prismjs": "^1.27.0",
     "rxjs": "^7.4.0",
     "rxjs-compat": "^6.6.7",
     "tether": "^2.0.0",