Fix not rendered markdown link in docs

The markdown links are not rendered properly on [the website](https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm/).
I replace them with html anchor tags to fix this weird issue.

Author: yechs

content/en/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm.md

@@ -11,9 +11,11 @@ weight: 30
 <img src="https://raw.githubusercontent.com/kubernetes/kubeadm/master/logos/stacked/color/kubeadm-stacked-color.png" align="right" width="150px">
 Using `kubeadm`, you can create a minimum viable Kubernetes cluster that conforms to best practices.
 In fact, you can use `kubeadm` to set up a cluster that will pass the
-[Kubernetes Conformance tests](https://kubernetes.io/blog/2017/10/software-conformance-certification).
+<a href="https://kubernetes.io/blog/2017/10/software-conformance-certification">Kubernetes Conformance tests</a>.
+
 `kubeadm` also supports other cluster lifecycle functions, such as
-[bootstrap tokens](/docs/reference/access-authn-authz/bootstrap-tokens/) and cluster upgrades.
+<a href="/docs/reference/access-authn-authz/bootstrap-tokens/">bootstrap tokens</a>
+and cluster upgrades.
 
 The `kubeadm` tool is good if you need: