enable-tls-for-mysql-client: add info about rotation of X.509 TLS certs

[dveeden]

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This is similar to #2930

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[dveeden]

The CI error is probably caused by a docker outage: https://www.dockerstatus.com/

[Oreoxmt]

Rest LGTM

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-10-20 10:00:12.304995997 +0000 UTC m=+693118.382248567: ☑️ agreed by Oreoxmt.