Remove @types/node 12 resolution

See DefinitelyTyped/DefinitelyTyped#44946

Author: nhooyr

package.json

@@ -59,7 +59,6 @@
     "typescript": "4.0.2"
   },
   "resolutions": {
-    "@types/node": "^12.12.7",
     "safe-buffer": "^5.1.1",
     "vfile-message": "^2.0.2"
   },