Bump prismjs from 1.17.1 to 1.23.0

Bumps [prismjs](https://github.com/PrismJS/prism) from 1.17.1 to 1.23.0.
- [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/v1.17.1...v1.23.0)

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

package.json

@@ -13,7 +13,7 @@
     "mathjax-node": "^2.1.1",
     "ncp": "^2.0.0",
     "node-prismjs": "^0.1.2",
-    "prismjs": "^1.16.0",
+    "prismjs": "^1.23.0",
     "rss": "^1.2.2",
     "showdown": "^1.9.0"
   },