Add Chrome Credential Management API example

[tribou]

If a user is browsing our app using Google Chrome, accessing the Credential Management API to at least start the auth process by getting an email could be a good improvement in UX. See Zillow and Starbucks online apps for reference...

We should implement an example of any best practices available from this API.

ref: https://developers.google.com/web/fundamentals/security/credential-management/