Update dependency express to ^4.17.3

Author: renovate-bot

package.json

@@ -54,7 +54,7 @@
     "@sourcegraph/typescript-language-server": "^0.3.7-fork",
     "abort-controller": "^3.0.0",
     "axios": "^0.19.2",
-    "express": "^4.17.1",
+    "express": "^4.17.3",
     "fast-glob": "^3.2.2",
     "got": "^10.6.0",
     "highlight.js": "^9.18.1",