Bump loki-operator subscription to stable-6.6 channel

The stable-6.4 channel is no longer available in the CRC redhat-operators
catalog, which caused Loki install to fail and blocked OpenStackControlPlane
readiness in multinode-cloudkitty jobs.

Signed-off-by: Daniel Pawlik <dpawlik@redhat.com>

Author: danpawlik

ci/deploy-loki-for-ck.yaml

@@ -25,7 +25,7 @@ metadata:
   name: loki-operator
   namespace: openshift-operators-redhat
 spec:
-  channel: stable-6.4
+  channel: stable-6.6
   name: loki-operator
   source: redhat-operators
   sourceNamespace: openshift-marketplace