Bump prismjs and react-syntax-highlighter

Bumps [prismjs](https://github.com/PrismJS/prism) and [react-syntax-highlighter](https://github.com/react-syntax-highlighter/react-syntax-highlighter). These dependencies needed to be updated together.

Updates `prismjs` from 1.17.1 to 1.29.0
- [Release notes](https://github.com/PrismJS/prism/releases)
- [Changelog](https://github.com/PrismJS/prism/blob/master/CHANGELOG.md)
- [Commits](PrismJS/prism@v1.17.1...v1.29.0)

Updates `react-syntax-highlighter` from 12.2.1 to 15.5.0
- [Release notes](https://github.com/react-syntax-highlighter/react-syntax-highlighter/releases)
- [Changelog](https://github.com/react-syntax-highlighter/react-syntax-highlighter/blob/master/CHANGELOG.MD)
- [Commits](react-syntax-highlighter/react-syntax-highlighter@v12.2.1...15.5.0)

---
updated-dependencies:
- dependency-name: prismjs
  dependency-type: indirect
- dependency-name: react-syntax-highlighter
  dependency-type: direct:production
...

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

Author: dependabot[bot]

package-lock.json

@@ -54,7 +54,7 @@
     "react-scripts": "3.4.0",
     "react-scroll": "^1.7.15",
     "react-swipeable-views": "^0.13.3",
-    "react-syntax-highlighter": "^12.2.1",
+    "react-syntax-highlighter": "^15.5.0",
     "react-touch-carousel": "^0.9.3",
     "react-vimeo": "^2.0.0",
     "react-youtube": "^7.9.0",