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](expressjs/express@4.17.1...4.17.3)

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

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

Author: dependabot[bot]

package.json

@@ -16,7 +16,7 @@
     "@babel/preset-env": "^7.10.4",
     "babel-loader": "^8.1.0",
     "chokidar": "^3.4.1",
-    "express": "^4.17.1",
+    "express": "^4.17.3",
     "@hotwired/stimulus": "^3.2.0",
     "@hotwired/stimulus-webpack-helpers": "^1.0.0",
     "webpack": "^4.43.0",