chore: migrate from k8s.gcr.io to registry.k8s.io (#376)

Author: ahmedwaleedmalik

config/core/config-observability.yaml

@@ -42,7 +42,7 @@ data:
     # logging.fluentd-sidecar-image provides the fluentd sidecar image
     # to inject as a sidecar to collect logs from /var/log.
     # Must be presented if logging.enable-var-log-collection is true.
-    logging.fluentd-sidecar-image: k8s.gcr.io/fluentd-elasticsearch:v2.0.4
+    logging.fluentd-sidecar-image: registry.k8s.io/fluentd-elasticsearch:v2.0.4
 
     # logging.fluentd-sidecar-output-config provides the configuration
     # for the fluentd sidecar, which will be placed into a configmap and