[tls] Change CA time check to minutes instead of hours

[Deydra71]

This change allows to use CA certs duration shorter than 1 day, e.g.:

  tls:
    ingress:
      ca:
        duration: 2h0m0s
      cert:
        duration: 1h0m0s
    podLevel:
      internal:
        ca:
          duration: 2h0m0s
        cert:
          duration:  1h0m0s
      libvirt:
        ca:
          duration: 2h0m0s
        cert:
          duration:  1h0m0s
      ovn:
        ca:
          duration: 2h0m0s
        cert:
          duration:  1h0m0s

[openshift-ci[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Deydra71, stuggi

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[Deydra71]

/test openstack-operator-build-deploy-kuttl

[Deydra71]

/test openstack-operator-build-deploy-kuttl