Bump katex from 0.11.1 to 0.13.18

Bumps [katex](https://github.com/KaTeX/KaTeX) from 0.11.1 to 0.13.18.
- [Release notes](https://github.com/KaTeX/KaTeX/releases)
- [Changelog](https://github.com/KaTeX/KaTeX/blob/master/CHANGELOG.md)
- [Commits](KaTeX/KaTeX@v0.11.1...v0.13.18)

---
updated-dependencies:
- dependency-name: katex
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

package.json

@@ -226,7 +226,7 @@
 		"jsdom": "^16.6.0",
 		"jsrsasign": "^10.4.0",
 		"juice": "^8.0.0",
-		"katex": "^0.11.1",
+		"katex": "^0.13.18",
 		"ldap-escape": "^2.0.5",
 		"ldapjs": "^2.3.1",
 		"less": "https://github.com/meteor/less.js/tarball/8130849eb3d7f0ecf0ca8d0af7c4207b0442e3f6",