bug(auth,event-broker): Don't allow invalid client ids through

[dschom]

Because

• Client Ids with values 'none' were making their way to the event broker
• This was happening because 'none' is a valid value for service, and service is sometimes a fallback for client id.

This pull request

• Creates stricter checks on what a valid client id is.

Issue that this pull request solves

Closes: FXA-9802

Checklist

Put an x in the boxes that apply

• [x] My commit is GPG signed.
• [ ] If applicable, I have modified or added tests which pass locally.
• [ ] I have added necessary documentation (if appropriate).
• [ ] I have verified that my changes render correctly in RTL (if appropriate).

Other information (Optional)

Note that FXA-9802 has already been 'fixed'. For some reason sentry is grouping a couple validation errors together that are actually unrelated. Unfortunately, I can't reconcile this in Sentry, which is why I'm pulling this in as a part 2 fix.

[bbangert]

Do we know where in FxA we're sending these from? We could log these in the mean-time to try and track down more details around them to find where/why they aren't having this populated during send.