Fix example to include directives required for alerting

[matt-simons]

- What I did
Updated the example to include the directives documented here: https://docs.openshift.com/container-platform/4.5/installing/install_config/installing-customizing.html#installation-special-config-crony_installing-customizing

Without rtcsync in particular an alert called NodeClockNotSynchronising will trigger in Openshift, as discussed in Case 02763639

- How to verify it

Apply the example as is (with a valid NTP server) and the alert will fire.

- Description for the changelog
Fix example to include directives required for alerting

[openshift-ci-robot]

Hi @matt-simons. Thanks for your PR.

I'm waiting for a openshift member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[cgwalters]

Thanks!
/approve
/lgtm
/ok-to-test
/skip

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cgwalters, matt-simons

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• OWNERS [cgwalters]

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[openshift-bot]

/retest

Please review the full test history for this PR and help us cut down flakes.

[openshift-ci-robot]

@matt-simons: The following tests failed, say /retest to rerun all failed tests:

Test name	Commit	Details	Rerun command
ci/prow/e2e-ovn-step-registry	3828525	link	/test e2e-ovn-step-registry
ci/prow/e2e-aws-workers-rhel7	3828525	link	/test e2e-aws-workers-rhel7

Full PR test history. Your PR dashboard.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. I understand the commands that are listed here.