Add note on namespace management in GitOps example (#100)

resource-definitions/k8s-cluster-git/runtime/README.md

@@ -5,6 +5,8 @@ This section contains example Resource Definitions for connecting to a Git repos
 It also provides a solution to specify the non GitOps-cluster where the GitOps deploys workloads.  
 To retrieve the status of deployed workloads, the Orchestrator searches for a `k8s-cluster` Resource with the Id `k8s-cluster-runtime`. If it doesn't find this resource, it defaults to the `k8s-cluster` resource with the Id `k8s-cluster`. When the default cluster is a GitOps-managed cluster, an additional non-GitOps cluster is required to gather runtime information for workloads deployed by the GitOps operator. This example demonstrates that process.
 
+The namespace name where the Orchestrator will look for the Kubernetes objects to gather runtime information is retrieved from the Active Resource of type `k8s-namespace`. Note that in GitOps mode, the namespace is an externally managed Resource, i.e. the Platform Orchestrator does not create the namespace. It is recommended to use a namespace Resource Definition based on the [Echo Driver](https://developer.humanitec.com/integration-and-extensions/drivers/generic-drivers/echo/) to reflect this fact. This also means that any customization of the namespace, such as adding specific labels, must be managed externally.
+
 The chart illustrates the setup. Because `k8s-cluster` is an [_implicit_  Resource Type](https://developer.humanitec.com/platform-orchestrator/reference/resource-types/#resource-type-use), one such Resource is always matched for any Deployment. This creates the Resource representing the GitOps cluster, using the `k8s-cluster-git` Driver. That resource co-provisions another Resource of type `k8s-cluster` with the Id `k8s-cluster-runtime` and the `k8s-cluster-gke` Driver, representing the runtime cluster.
 
 ```mermaid