chore(deps-dev): bump @types/node from 15.3.1 to 15.6.0

Bumps [@types/node](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/node) from 15.3.1 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[bot] <support@github.com>

package.json

@@ -31,7 +31,7 @@
   },
   "devDependencies": {
     "@types/jest": "^26.0.23",
-    "@types/node": "^15.3.1",
+    "@types/node": "^15.6.0",
     "@typescript-eslint/parser": "^4.24.0",
     "@vercel/ncc": "^0.28.5",
     "eslint": "^7.26.0",