Node v18 is that current LTS release of node and v18.20.3 is the latest
release of v18.
This change means that emsdk is no longer installable on Ubuntu/Bionic
18.04, and we now require Ubuntu/Focal 20.04.
See: #1183Fixes: #1173
The newer versions of eslint require 14.17.0 or above. This
updates our node version to the latest in the 14.XX series.
I don't expect any user-visible changes.