chore(deps-dev): bump @types/node from 14.14.7 to 15.12.2

Bumps [@types/node](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/node) from 14.14.7 to 15.12.2.
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/node)

---
updated-dependencies:
- dependency-name: "@types/node"
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

package-lock.json

@@ -32,7 +32,7 @@
     "@json-schema-tools/meta-schema": "^1.6.10",
     "@types/isomorphic-fetch": "0.0.35",
     "@types/jest": "^26.0.23",
-    "@types/node": "^14.17.3",
+    "@types/node": "^15.12.2",
     "jest": "^24.9.0",
     "ts-jest": "^24.3.0",
     "tslint": "^6.1.3",