log: instrument telemetry when PII redaction is enabled

[thtruo]

We currently have no tracking when a user has enabled PII redaction for the server or client. Having this telemetry will help us understand specifically the usage and adoption around the new PII redaction option, and over the long term, give us more insight into which clusters utilize at least one security related feature.

[blathers-crl]

Hi @thtruo, I've guessed the C-ategory of your issue and suitably labeled it. Please re-label if inaccurate.

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