Adds RKE2 to list of providers

Signed-off-by: Dharmit Shah <[email protected]>

Author: dharmit

docs/book/src/reference/providers.md

@@ -11,6 +11,7 @@ updated info about which API version they are supporting.
 - [Kubeadm](https://github.com/kubernetes-sigs/cluster-api/tree/main/bootstrap/kubeadm)
 - [MicroK8s](https://github.com/canonical/cluster-api-bootstrap-provider-microk8s)
 - [Oracle Cloud Native Environment (OCNE)](https://github.com/verrazzano/cluster-api-provider-ocne)
+- [RKE2](https://github.com/rancher/cluster-api-provider-rke2)
 - [Talos](https://github.com/siderolabs/cluster-api-bootstrap-provider-talos)
 - [K3s](https://github.com/cluster-api-provider-k3s/cluster-api-k3s)
 - [k0smotron/k0s](https://github.com/k0sproject/k0smotron)
@@ -21,6 +22,7 @@ updated info about which API version they are supporting.
 - [MicroK8s](https://github.com/canonical/cluster-api-control-plane-provider-microk8s)
 - [Nested](https://github.com/kubernetes-sigs/cluster-api-provider-nested)
 - [Oracle Cloud Native Environment (OCNE)](https://github.com/verrazzano/cluster-api-provider-ocne)
+- [RKE2](https://github.com/rancher/cluster-api-provider-rke2)
 - [Talos](https://github.com/siderolabs/cluster-api-control-plane-provider-talos)
 - [Kamaji](https://github.com/clastix/cluster-api-control-plane-provider-kamaji)
 - [K3s](https://github.com/cluster-api-provider-k3s/cluster-api-k3s)