Change Default Env to standardize TLD and Port

[corysabol]

The default env needs to have the api host changed to https://api.cors.test:8443 in order for the labs to work as we are standardizing on .test and 8443.

[corysabol]

musashi-js/client.cors.demo/app.js

Line 9 in 1576d6b

const apiHost = process.env.CORS_API_HOST || 'api.cors.dem';

We can change this logic on this line. But also we should feed in a default set of env vars anyhow.