chore(deps): update dependency @types/which to v2

Author: renovate-bot

mock/package-lock.json

@@ -43,7 +43,7 @@
     "@types/node": "11.15.5",
     "@types/swagger-parser": "4.0.3",
     "@types/wait-on": "5.2.0",
-    "@types/which": "1.3.2",
+    "@types/which": "2.0.0",
     "axios": "0.19.2",
     "depcheck": "1.3.1",
     "gts": "1.1.2",