Update dependency @types/express to v4.17.3

Author: renovate-bot

package-lock.json

@@ -23,7 +23,7 @@
     "@sourcegraph/prettierrc": "^2.2.0",
     "@sourcegraph/tsconfig": "^3.0.0",
     "@sourcegraph/tslint-config": "^12.3.1",
-    "@types/express": "4.17.0",
+    "@types/express": "4.17.3",
     "@types/morgan": "1.7.37",
     "@types/node-fetch": "2.5.4",
     "get-graphql-schema": "^2.1.1",