Test runner environment

[germain-gg]

@PTaylour reported a few errors when running the unit test. It reportedly fails on the window object.

It looks odd as jest as a testEnvironment set by default to be jsdom. You can see the initial conversation on #110

https://jestjs.io/docs/en/configuration.html#testenvironment-string

We need to investigate the failure and setup the right mocks.

[PTaylour]

Cheers @gsouquet. Further context: this doesn't effect any of the current tests. But we were looking to add a new test that checked videocontext was added to window for browser envs