fix(cert-manager): resolve reconciliation issues with enableCertificateOwnerRef

[valen-mascarenhas14]

Fixes #331

PR Description

Problem

The operator cannot reconcile ETCD clusters when using cert-manager configured with enableCertificateOwnerRef=true. This manifests in two ways:

1. Certificate creation fails due to invalid duration parsing:

   ERROR Failed to create Client Certificate. error: "failed to parse ValidityDuration: time: unknown unit \"d\" in duration \"365d\""
   

2. Owner reference conflicts when cert-manager's enableCertificateOwnerRef=true sets Certificate as the controller owner of TLS secrets, preventing the operator from managing them.

Root Causes

Duration Parsing Issue:
Go's time.ParseDuration doesn't support day units (d), but the sample configuration and API documentation use day-based durations like "365d" and "100d12h".

Owner Reference Issue:
When enableCertificateOwnerRef=true, cert-manager sets itself as the controller owner of TLS secrets. The operator was attempting to overwrite this ownership, causing reconciliation failures.

Solution

1. Duration Parsing Fix:
Enhanced parseValidityDuration to automatically convert day units to hours:

• "365d" → "8760h" (365 × 24 hours)
• "100d12h" → "2412h" (100 × 24 + 12 hours)
• Maintains backward compatibility with hour-based durations

2. Owner Reference Fix:
Modified secret ownership logic to:

• Skip ownership patching when a controller owner already exists
• Preserve cert-manager's ownership of TLS secrets
• Log informational messages instead of errors

[k8s-ci-robot]

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[k8s-ci-robot]

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