www/node: Update 15.2.0 -> 15.2.1

https://nodejs.org/en/blog/release/v15.2.1/

This is a security release. See
https://nodejs.org/en/blog/vulnerability/november-2020-security-releases/

MFH: 2020Q4
Security: ad792169-2aa4-11eb-ab71-0022489ad614
Sponsored by: Miles AS