chore: Conditionally deploy sandbox controller

Wrap the sandbox controller deployment manifest in a conditional block.
This allows enabling or disabling the deployment based on the cluster's
'sandbox_controller_enabled' configuration item.

Author: ponimas

cluster/manifests/sandbox-controller/deployment.yaml

@@ -1,6 +1,7 @@
 # {{ $image := "container-registry.zalando.net/gwproxy/sandbox-controller:main-8" }}
 # {{ $version := index (split $image ":") 1 }}
 
+{{ if eq .Cluster.ConfigItems.sandbox_controller_enabled "true" }}
 apiVersion: apps/v1
 kind: Deployment
 metadata:
@@ -40,3 +41,4 @@ spec:
             requests:
               cpu: 50m
               memory: 0.3Gi
+{{ end }}