There seems to be no good reason for testing on Node.js other than
the current LTS. Moreover, npm@6 has a wontfix issue when upgrading
to 8.4 on Windows, which requires a complex workaround: https://github.com/npm/cli/issues/4341#issuecomment-1040608101.
So avoid it by simply not supporting it.
And enable the module that really uses WebAssembly extensions for the
releases by running the new "npm run build:dual-wasm" command, which
sets the ENABLE_WASM_EXTENSIONS=true environment variable.
`lerna` is a bit stale, and as such it currently has some outdated
dependencies which Dependabot warns on.
Fortunately, npm 7 supports monorepos natively, via "workspaces". So
simply replace `lerna` with this feature. The migration is pretty
neat and requires a very little invervention.
Because Node.js 14 comes with npm 6 by default, upgrade it manually
as shown in https://github.com/bahmutov/npm-install/issues/103#issuecomment-931226602.
As usual, also bump its helper crates (`js-sys`, `wasm-bindgen-futures`)
to the latest versions, except for `web-sys` which is locked by wgpu
to 0.3.50.
Also bump its helper crates (js-sys, wasm-bindgen-futures) to the
latest versions, except for web-sys which seems to be locked by wgpu
to one version before the latest (0.3.50).
* Remove `buildProduction` as it was equivalent to `build`.
* Fix `build:avm_debug` and change it to `build:debug`, which also
disables Webpack optimizations.