Bump @types/node from 13.13.5 to 15.6.0

Bumps [@types/node](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/node) from 13.13.5 to 15.6.0.
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/node)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -20,7 +20,7 @@
   "devDependencies": {
     "@types/jest": "~25.2.1",
     "@types/mkdirp": "^0.5.2",
-    "@types/node": "^13.1.8",
+    "@types/node": "^15.6.0",
     "@types/uuid": "^3.4.4",
     "command-line-args": "^5.0.2",
     "coveralls": "^3.0.2",