Bump express from 4.17.1 to 4.17.3

Bumps [express](https://github.com/expressjs/express) from 4.17.1 to 4.17.3.
- [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/4.17.1...4.17.3)

---
updated-dependencies:
- dependency-name: express
  dependency-type: direct:production
...

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

package.json

@@ -14,7 +14,7 @@
     "dependencies": {
         "dotenv": "^8.2.0",
         "ejs": "^3.1.7",
-        "express": "^4.17.1",
+        "express": "^4.17.3",
         "socket.io": "^2.4.0"
     },
     "devDependencies": {