Bump express from 4.19.2 to 4.20.0 in /xterm (#470)

Bumps [express](https://github.com/expressjs/express) from 4.19.2 to 4.20.0.
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/master/History.md)
- [Commits](expressjs/express@4.19.2...4.20.0)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

xterm/package.json

@@ -9,7 +9,7 @@
   "author": "",
   "license": "MIT",
   "dependencies": {
-    "express": "4.19.2",
+    "express": "4.20.0",
     "express-ws": "3.0.0",
     "node-pty": "0.7.0"
   }