Replace "clients" with "users" in authentication docs

[ricab]

Description of documentation issue or suggestion Docs relating to authentication usually describe clients being trusted. Here's an example. But it is not clients themselves that are trusted, it is the users who run them.

Proposal to fix issue or enact suggestion Reword docs as needed to replace the notion of authenticating clients with authenticating users.

Additional context

Note that:

• A user that is trusted can use either the CLI or the GUI clients (or any other client, provided they correctly pass on their certificate).
• A client that authenticated when running as a given user, will not be considered authenticated when running as another user (unless that user is also trusted).

[ayaankhan98]

Hi @ricab I can help with this. seems like a straight forward issue. Let me know I can give a PR.

[ricab]

Hi @ayaankhan98, you can, of course! Thanks again for your interest.

[ayaankhan98]

@ricab I have created the PR, please review and let me know if it needs any changes.