Add node 15.0.0 release to browser data (#7015)
Add node 15.0.0 release to browser data (#7015)

See https://nodejs.org/en/blog/release/v15.0.0/
chrisdavidmills/browser-compat-data,mdn/browser-compat-data,chrisdavidmills/browser-compat-data,mdn/browser-compat-data