New authentication patterns cheat sheet

[dadrus]

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This PR contains an update I had originally planned as a contribution to the Microservice Security Cheat Sheet. Since the resulting content became too lengthy for a cheat sheet, I was encouraged by @jmanico and other Cheat Sheet Project contributors/maintainers to split it into separate PRs for each part.

This particular PR includes the content from my Authentication Patterns blog post.

I’m still not sure where to place the content from my Core Concepts blog post.

At least, this is a start and should enable better discussion of the material.

[jmanico]

This is an amazing piece of work. This is the first in a series of architecture cheatsheets for security. Can everyone take a close look at this?

I would love to see if we can reduce the size of this some without losing fidelity - curious what you think @mackowski and @szh