Bump express from 4.16.3 to 4.17.1

Bumps [express](https://github.com/expressjs/express) from 4.16.3 to 4.17.1.
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/master/History.md)
- [Commits](https://github.com/expressjs/express/compare/4.16.3...4.17.1)

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

package.json

@@ -43,7 +43,7 @@
     "codemirror": "^5.51.0",
     "cookie-parser": "^1.4.4",
     "create-react-class": "^15.6.3",
-    "express": "^4.13.3",
+    "express": "^4.17.1",
     "jwt-simple": "^0.5.6",
     "lodash": "^4.17.15",
     "marked": "^0.8.0",