Fix(KGO): Duplicate text and missing namespace text (#2970)

* duplicate conent, and missing namespace

* Update app/_includes/k8s/kong-namespace.md

Co-authored-by: lena-larionova <54370747+lena-larionova@users.noreply.github.com>

---------

Co-authored-by: lena-larionova <54370747+lena-larionova@users.noreply.github.com>

Author: Guaris

app/_how-tos/operator-get-started-kic-create-gateway.md

@@ -71,6 +71,9 @@ spec:
 ```
 
 {:data-deployment-topology='on-prem'}
+
+{% include k8s/kong-namespace.md %}
+
 ## GatewayConfiguration
 
 ```yaml

app/_how-tos/operator-get-started-kic-install.md

@@ -40,11 +40,12 @@ tldr:
 kubectl apply -f https://github.com/kubernetes-sigs/gateway-api/releases/download/v{{ gwapi_version }}/standard-install.yaml
 ```
 
+{% include k8s/kong-namespace.md %}
+
 ## Install {{ site.gateway_operator_product_name }}
 
 {% include prereqs/products/operator.md raw=true v_maj=1 %}
 
-{% include k8s/cert-manager.md %}
 
 ## Wait for {{ site.gateway_operator_product_name }} to be ready
 

app/_includes/k8s/kong-namespace.md

@@ -0,0 +1,7 @@
+## Create the `kong` namespace
+
+Create the `kong` namespace in your Kubernetes cluster, which is where the demo will run:
+
+```sh
+kubectl create namespace kong
+```