chore: remove (deprecate) all manifests from deploy/single (#4970)

.gitattributes

@@ -1,5 +1,6 @@
 **/zz_generated*.go linguist-generated=true
 pkg/clientset/** linguist-generated=true
 deploy/single/** linguist-generated=true
+test/e2e/manifests/** linguist-generated=true
 docs/api-reference.md linguist-generated=true
 internal/dataplane/parser/testdata/golden/**/*_golden.yaml linguist-generated=true

CHANGELOG.md

@@ -117,10 +117,9 @@ Adding a new version? You'll need three changes:
 - `deploy/single/all-in-one-dbless-legacy.yaml` manifest is removed.
   It was already deprecated in 2.9
   [#4866](https://github.com/Kong/kubernetes-ingress-controller/pull/4866)
-- `deploy/single/all-in-one-dbless-enterprise.yaml` manifest is removed.
-  It's nearly identical to `deploy/single/all-in-one-dbless-k4k8s-enterprise.yaml`
-  which is used in the official docs.
-  [#4873](https://github.com/Kong/kubernetes-ingress-controller/pull/4873)
+- All manifests from `deploy/single` are no longer supported as installation
+  method and were removed, please use Helm chart or Kong Gateway Operator instead.
+  [#4866](https://github.com/Kong/kubernetes-ingress-controller/pull/4866), [#4873](https://github.com/Kong/kubernetes-ingress-controller/pull/4873), [#4970](https://github.com/Kong/kubernetes-ingress-controller/pull/4970), 
 - Credentials now use a `konghq.com/credential` label to indicate
   credential type instead of the `kongCredType` field. This allows controller
   compontents to avoid caching unnecessary Secrets. The `kongCredType` field is

README.md

@@ -44,15 +44,11 @@ a hosted Kubernetes service like [GKE](https://cloud.google.com/kubernetes-engin
 Setting up Kong for Kubernetes is as simple as:
 
 ```shell
-# using YAMLs
-$ kubectl apply -f https://raw.githubusercontent.com/Kong/kubernetes-ingress-controller/latest/deploy/single/all-in-one-dbless.yaml
+# Using Helm
+helm repo add kong https://charts.konghq.com
+helm repo update
 
-# or using Helm
-$ helm repo add kong https://charts.konghq.com
-$ helm repo update
-
-# Helm 3
-$ helm install kong/kong --generate-name --set ingressController.installCRDs=false
+helm install kong/kong --generate-name --set ingressController.installCRDs=false
 ```
 
 Once installed, please follow the [Getting Started guide][docs-konghq-getting-started-guide]