http => https redirect

[brunobowden]

Summary

Any links using the non-secure http protocol should be redirected permanently to https.

Currently shows 404:
http://staging.whocoronavirus.org/app

Should redirect to working page:
https://staging.whocoronavirus.org/app

Checklist:

• Searched the existing issues to ensure you are not creating a duplicate.
• Followed the Contributor Guidelines.