This issue was reported

https://issues.redhat.com/browse/OCPBUGS-59528

The customer configured a wrong certificate in the image.config.openshift.io cluster resource, the they fixed the certificates and they expect the certificate to be correctly deployed without having to restart the controller pod.

It will not be fixed in 4.14 since it is not actually a bug, nevertheless a new PR will be submitted in 4.20 to cover this scenario.

We need to create a new test case to cover it

It can be something like:
1. Create a CM with a wrong cert
2. Configure the CM in the image config resource
3. Check that the logs report a wrong cert
4. Fix the cert in the CM
5. Check that the cert is properly added

Everything we need is defined in the test cases
"OCP-75521-Log details for malformed certificates. No infinite loop"
and
"OCP-66048-Check image registry user bundle certificate"