Bump prismjs from 1.29.0 to 1.30.0 in /themes/custom-theme

Bumps [prismjs](https://github.com/PrismJS/prism) from 1.29.0 to 1.30.0.
- [Release notes](https://github.com/PrismJS/prism/releases)
- [Changelog](https://github.com/PrismJS/prism/blob/master/CHANGELOG.md)
- [Commits](https://github.com/PrismJS/prism/compare/v1.29.0...v1.30.0)

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

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

themes/custom-theme/package.json

@@ -44,7 +44,7 @@
     "flexsearch": "^0.7.31",
     "normalize.css": "^8.0.1",
     "prism-themes": "^1.9.0",
-    "prismjs": "^1.29.0",
+    "prismjs": "^1.30.0",
     "simple-icons": "^9.19.0",
     "typeface-fira-code": "^1.1.13",
     "typeface-roboto-slab": "^1.1.13"