Wrong secret name in kubevirt-manager-certificate

Summary

kubevirt-manager-certificate set a wrong secret name (keycloak-tls). kubevirt-manager-tls would be better

related references

https://gitlab.com/sylva-projects/sylva-core/-/blob/82f49a37903d3d124e11592ed567130260902d0c/kustomize-units/kubevirt-manager/kubevirt-manager-certificate.yaml#L20