JS: Mock FileSaver when using Cypress

[IanLondon]

Overview

It's bad to modify application code to support tests, let's avoid it!

Acceptance criteria

• Remove references to process.env.CYPRESS / global.Cypress from PD/LC application code
• Rely on webpack to mock FileSaver when process.env.CYPRESS === '1'

Implementation details

This override should happen using a mock for FileSaver that webpack (using the resolve) config or babel (using babel-plugin-module-resolver) shims in when the environment is Cypress rather than putting the override logic in application code

https://github.com/_render_node/MDI0OlB1bGxSZXF1ZXN0UmV2aWV3Q29tbWVudDQxMjM2NzQ3Ng==/comments/review_comment_