Bump material-design-icons-iconfont from 6.4.1 to 6.4.2

Bumps [material-design-icons-iconfont](https://github.com/jossef/material-design-icons-iconfont) from 6.4.1 to 6.4.2.
- [Release notes](https://github.com/jossef/material-design-icons-iconfont/releases)
- [Commits](https://github.com/jossef/material-design-icons-iconfont/compare/6.4.1...v6.4.2)

---
updated-dependencies:
- dependency-name: material-design-icons-iconfont
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

package.json

@@ -77,7 +77,7 @@
     "jquery": "^3.6.0",
     "jquery.cookie": "^1.4.1",
     "jr-qrcode": "^1.0.7",
-    "material-design-icons-iconfont": "^6.4.1",
+    "material-design-icons-iconfont": "^6.4.2",
     "materialize-css": "^0.98.1",
     "mathjax": "^3.1.2",
     "mousetrap": "^1.6.0",