deps: upgrade npm to 7.0.8

PR-URL: https://github.com/nodejs/node/pull/35953


Reviewed-By: Ruy Adorno <ruyadorno@github.com>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>