vtk-js: Can't use @kitware/vtk.js with Jest

High-level description

@kitware/vtk.js seems to be built incorrectly, test frameworks such as Jest are unable to parse the package and throw an error.

I think the library should be compiled with ES5 as target (at least, for the module entry point), this way better interoperability will be provided.

Steps to reproduce

1. Download the sample project d8lhv.zip, or setup a Create React App and import any @kitware/vtk.js module from the package;
2. Add "node_modules/(?!(@kitware)/)" to the transformIgnorePatterns in package.json > jest
3. Create a test file and import App.js
4. Run yarn test

Detailed behavior

Jest fails with the following error:

  FAIL  src/App.test.js
  ● Test suite failed to run

    /Users/federicozivolo/Downloads/d8lhv/node_modules/@kitware/vtk.js/Common/Core/Math.js: Cannot use import statement outside a module

      at interopRequire (node_modules/babel-plugin-macros/dist/index.js:86:15)
      at applyMacros (node_modules/babel-plugin-macros/dist/index.js:208:17)
      at ImportDeclaration (node_modules/babel-plugin-macros/dist/index.js:114:28)

Expected behavior

Jest should be able to import the library without erroring.

Environment

• vtk.js: 18.4.
• OS: macOS 11.4
• Browser: Node 12.20.0