feat: allow configuration of certificate duration and expiring check time

[zekiyeaydemir]

Allowed the configuration of certificationDuration and expiringCheckThreshold parameters.

Closes: #1691

[github-actions]

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[leonardoce]

Hi @zekiyeaydemir. We want to merge this in the next release.
Can you please test what happens when you set an incorrect value for CERTIFICATE_DURATION, for example, a string instead of a number? We need to be sure we'll have an understandable error message.
Thanks!

[litaocdl]

/test limit=local

[litaocdl]

/test limit=local d=push

[github-actions]

@litaocdl, here's the link to the E2E on CNPG workflow run: https://github.com/cloudnative-pg/cloudnative-pg/actions/runs/8274281348

[litaocdl]

Hi @zekiyeaydemir. We want to merge this in the next release. Can you please test what happens when you set an incorrect value for CERTIFICATE_DURATION, for example, a string instead of a number? We need to be sure we'll have an understandable error message. Thanks!

if the invalid value is set for cetification duration or threhold, default will be used and info msg will reports in operator log

"Skipping invalid integer value parsing configuration","field":"CertificateDuration","value":"100s"

[litaocdl]

/ok-to-merge