Review current HTTP Headers, DNS, etc...

So far seems like we can invest some time to improve several things:

- The HTTP headers in the website and discuss if we want to apply headers like: Content Security Policy, Strict Transport Policy, X-Content-Type-Options, X-Frame-Options, X-XSS-Protection...
- CA Authorization in the TLS layer
- Enable HSTS
- Add a `Security.Txt`file pointing to the current project security policy?

I used [Web Check](https://web-check.xyz/check/https%3A%2F%2Fexpressjs.com) to do a fast review, so this is not yet an exhaustive list