Update dependency @types/node to v12.20.55

Author: renovate[bot]

package-lock.json

@@ -33,7 +33,7 @@
   "devDependencies": {
     "@types/cosmiconfig": "5.0.3",
     "@types/jest": "24.9.1",
-    "@types/node": "12.12.31",
+    "@types/node": "12.20.55",
     "jest": "24.9.0",
     "rimraf": "3.0.2",
     "ts-jest": "24.3.0",