deps: update github.com/keptn/lifecycle-toolkit/keptn-cert-manager digest to 8c76404 #17822

Job	Run time
Prepare CI Run	4s
Build Docker Image (lifecycle-operator, lifecycle-operator/)	1m 12s
Build Docker Image (metrics-operator, metrics-operator/)	54s
Store tag of the built images	3s
Unit Tests (lifecycle-operator, lifecycle-operator/)	1m 9s
Build Docker Image (scheduler, scheduler/)	1m 16s
Unit Tests (metrics-operator, metrics-operator/)	52s
Build Docker Image (deno-runtime, runtimes/deno-runtime/)	14s
Unit Tests (scheduler, scheduler/)	20s
Build Docker Image (python-runtime, runtimes/python-runtime/)	22s
Unit Tests (certificate-operator, keptn-cert-manager/)	29s
Build Docker Image (certificate-operator, keptn-cert-manager/)	1m 13s
Component Tests / Component Tests	3m 23s
Integration Tests	0s
Integration Tests Lifecycle	0s
Integration Tests Allowed Namespaces	0s
Integration Tests Metrics	0s
End to End Tests	0s
Integration Tests Cert Manager	0s
Publish helm chart changes to charts repo	0s
Load Tests	0s
	11m 31s

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