chore(deps): bump prismjs from 1.19.0 to 1.21.0 in /website

Bumps [prismjs](https://github.com/PrismJS/prism) from 1.19.0 to 1.21.0.
- [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/v1.19.0...v1.21.0)

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

website/package-lock.json

@@ -7004,9 +7004,9 @@
       "dev": true
     },
     "prismjs": {
-      "version": "1.20.0",
-      "resolved": "https://registry.npmjs.org/prismjs/-/prismjs-1.20.0.tgz",
-      "integrity": "sha512-AEDjSrVNkynnw6A+B1DsFkd6AVdTnp+/WoUixFRULlCLZVRZlVQMVWio/16jv7G1FscUxQxOQhWwApgbnxr6kQ==",
+      "version": "1.21.0",
+      "resolved": "https://registry.npmjs.org/prismjs/-/prismjs-1.21.0.tgz",
+      "integrity": "sha512-uGdSIu1nk3kej2iZsLyDoJ7e9bnPzIgY0naW/HdknGj61zScaprVEVGHrPoXqI+M9sP0NDnTK2jpkvmldpuqDw==",
       "dev": true,
       "requires": {
         "clipboard": "^2.0.0"

website/yarn.lock

@@ -5136,9 +5136,9 @@ prepend-http@^2.0.0:
   integrity sha1-6SQ0v6XqjBn0HN/UAddBo8gZ2Jc=
 
 prismjs@^1.17.1:
-  version "1.19.0"
-  resolved "https://registry.yarnpkg.com/prismjs/-/prismjs-1.19.0.tgz#713afbd45c3baca4b321569f2df39e17e729d4dc"
-  integrity sha512-IVFtbW9mCWm9eOIaEkNyo2Vl4NnEifis2GQ7/MLRG5TQe6t+4Sj9J5QWI9i3v+SS43uZBlCAOn+zYTVYQcPXJw==
+  version "1.21.0"
+  resolved "https://registry.yarnpkg.com/prismjs/-/prismjs-1.21.0.tgz#36c086ec36b45319ec4218ee164c110f9fc015a3"
+  integrity sha512-uGdSIu1nk3kej2iZsLyDoJ7e9bnPzIgY0naW/HdknGj61zScaprVEVGHrPoXqI+M9sP0NDnTK2jpkvmldpuqDw==
   optionalDependencies:
     clipboard "^2.0.0"