Improve Kubernetes support documentation

Co-authored-by: Kevin Pollet <pollet.kevin@gmail.com>

docs/content/providers/kubernetes-crd.md

@@ -14,7 +14,9 @@ However, as the community expressed the need to benefit from Traefik features wi
 the Traefik engineering team developed a [Custom Resource Definition](https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/)
 (CRD) for an IngressRoute type, defined below, in order to provide a better way to configure access to a Kubernetes cluster.
 
-## Configuration Requirements
+## Requirements
+
+{!kubernetes-requirements.md!}
 
 !!! tip "All Steps for a Successful Deployment"
 
@@ -25,12 +27,6 @@ the Traefik engineering team developed a [Custom Resource Definition](https://ku
         * Apply the needed kubernetesCRD provider [configuration](#provider-configuration)
     * Add all necessary Traefik custom [resources](../reference/dynamic-configuration/kubernetes-crd.md#resources)
 
-!!! warning "Deprecated apiextensions.k8s.io/v1beta1 CRD"
-
-    The `apiextensions.k8s.io/v1beta1` CustomResourceDefinition is deprecated in Kubernetes `v1.16+` and will be removed in `v1.22+`.
-    
-    For Kubernetes `v1.16+`, please use the Traefik `apiextensions.k8s.io/v1` CRDs instead.
-
 !!! example "Installing Resource Definition and RBAC"
 
     ```bash

docs/content/providers/kubernetes-gateway.md

@@ -41,7 +41,9 @@ This provider is proposed as an experimental feature and partially supports the
     --experimental.kubernetesgateway=true --providers.kubernetesgateway=true #...
     ```
 
-## Configuration Requirements
+## Requirements
+
+{!kubernetes-requirements.md!}
 
 !!! tip "All Steps for a Successful Deployment"
 

docs/content/providers/kubernetes-ingress.md

@@ -13,7 +13,7 @@ it manages access to cluster services by supporting the [Ingress](https://kubern
 
 ## Requirements
 
-Traefik supports `1.23+` Kubernetes clusters.
+{!kubernetes-requirements.md!}
 
 ## Routing Configuration