feat(confluence): make synchrony readinessProbe timeoutSeconds configurable

[SuperWonjune]

Pull request description

The synchrony StatefulSet's readinessProbe has no way to configure timeoutSeconds, so it falls back to Kubernetes' default of 1s. In our production environment the probe occasionally fails under load, and we need the ability to tune this value per-cluster.
This adds synchrony.readinessProbe.timeoutSeconds (default 1, no behavior change) and wires it into the template — matching the pattern already used for confluence.readinessProbe / livenessProbe.

Checklist

• I have added unit tests
• I have applied the change to all applicable products
• The E2E test has passed (use e2e label)

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[SuperWonjune]

Thank you for your submission! Like many open source projects, we ask that you sign our CLA (Contributor License Agreement) before we can accept your contribution. If your email is listed below, please ensure that you sign the CLA with the same email address. **The following users still need to sign our CLA:**❌avgnrolfework-cloud

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FYI I have already assigned CLA as my username.