Add authentik, tidy up recipe-footer

Signed-off-by: David Young <davidy@funkypenguin.co.nz>

docs/kubernetes/cluster/digitalocean.md

@@ -76,4 +76,4 @@ That's it. You have a beautiful new kubernetes cluster ready for some action!
 
 [^1]: Do you live in the CLI? Install the kubectl autocompletion for [bash or zsh](https://kubernetes.io/docs/tasks/tools/install-kubectl-linux/) to make your life much easier!
 
---8<-- "recipe-footer.md"
+{% include 'recipe-footer.md' %}

docs/kubernetes/cluster/index.md

@@ -62,4 +62,4 @@ You'll learn more about how to care for and feed your cluster if you build it yo
 
 Go with a self-hosted cluster if you want to learn more, you'd rather spend time than money, or you've already got significant investment in local infructure and technical skillz.
 
---8<-- "recipe-footer.md"
+{% include 'recipe-footer.md' %}

docs/kubernetes/cluster/k3s.md

@@ -156,4 +156,4 @@ Cuddle your beautiful new cluster by running `kubectl cluster-info` [^1] - if th
 [^2]: Looking for your k3s logs? Under Ubuntu LTS, run `journalctl -u k3s` to show your logs
 [^3]: k3s is not the only "lightweight kubernetes" game in town. Minikube (*virtualization-based*) and mikrok8s (*possibly better for Ubuntu users since it's installed in a "snap" - haha*) are also popular options. One day I'll write a "mikrok8s vs k3s" review, but it doesn't really matter for our cluster operations - as I understand it, microk8s makes HA clustering slightly easire than k3s, but you get slightly less "out-of-the-box" in return, so mikrok8s may be more suitable for experience users / production edge deployments.
 
---8<-- "recipe-footer.md"
+{% include 'recipe-footer.md' %}