fix: suppress CKV_K8S_21 false positive on knowledge-explorer Helm chart

Checkov's helm framework renders the chart without a namespace override,
so metadata.namespace (set to .Release.Namespace, bound only at install
time) always resolves to "default" and trips CKV_K8S_21 on service.yaml,
deployment.yaml, and configmap.yaml even though the chart is
namespace-agnostic by design.

Suppressed via per-file checkov:skip comments, following the same
convention already used for the Cloud Run false positives in
deploy/gcp/cloudrun-service.yaml.

deploy/helm/knowledge-explorer/templates/configmap.yaml

@@ -1,3 +1,4 @@
+# checkov:skip=CKV_K8S_21:namespace is set to .Release.Namespace below, supplied at install time via `helm install -n <namespace>`; Checkov's helm-chart renderer runs without a namespace override and always resolves this to "default", which is a scanner artifact, not the deployed value
 apiVersion: v1
 kind: ConfigMap
 metadata:

deploy/helm/knowledge-explorer/templates/deployment.yaml

@@ -1,3 +1,4 @@
+# checkov:skip=CKV_K8S_21:namespace is set to .Release.Namespace below, supplied at install time via `helm install -n <namespace>`; Checkov's helm-chart renderer runs without a namespace override and always resolves this to "default", which is a scanner artifact, not the deployed value
 apiVersion: apps/v1
 kind: Deployment
 metadata:

deploy/helm/knowledge-explorer/templates/service.yaml

@@ -1,3 +1,4 @@
+# checkov:skip=CKV_K8S_21:namespace is set to .Release.Namespace below, supplied at install time via `helm install -n <namespace>`; Checkov's helm-chart renderer runs without a namespace override and always resolves this to "default", which is a scanner artifact, not the deployed value
 apiVersion: v1
 kind: Service
 metadata: