tools: add missing package-lock to clang-format

`npm ci` fails where there is no package-lock.json.
Also add the `node_modules` directory to .gitignore.

PR-URL: https://github.com/nodejs/node/pull/22500


Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>