docs/k8s: add prefix to (#5167)

Signed-off-by: Walter Poupore <walterp@tailscale.com>

docs/k8s/README.md

@@ -1,7 +1,11 @@
 # Overview
+
 There are quite a few ways of running Tailscale inside a Kubernetes Cluster, some of the common ones are covered in this doc.
+
 ## Instructions
+
 ### Setup
+
 1. (Optional) Create the following secret which will automate login.<br>
    You will need to get an [auth key](https://tailscale.com/kb/1085/auth-keys/) from [Tailscale Admin Console](https://login.tailscale.com/admin/authkeys).<br>
    If you don't provide the key, you can still authenticate using the url in the logs.
@@ -12,12 +16,13 @@ There are quite a few ways of running Tailscale inside a Kubernetes Cluster, som
    metadata:
      name: tailscale-auth
    stringData:
-     AUTH_KEY: tskey-...
+     TS_AUTH_KEY: tskey-...
    ```
 
 1. Tailscale (v1.16+) supports storing state inside a Kubernetes Secret.
 
    Configure RBAC to allow the Tailscale pod to read/write the `tailscale` secret.
+
    ```bash
    export SA_NAME=tailscale
    export TS_KUBE_SECRET=tailscale-auth
@@ -25,6 +30,7 @@ There are quite a few ways of running Tailscale inside a Kubernetes Cluster, som
    ```
 
 ### Sample Sidecar
+
 Running as a sidecar allows you to directly expose a Kubernetes pod over Tailscale. This is particularly useful if you do not wish to expose a service on the public internet. This method allows bi-directional connectivity between the pod and other devices on the Tailnet. You can use [ACLs](https://tailscale.com/kb/1018/acls/) to control traffic flow.
 
 1. Create and login to the sample nginx pod with a Tailscale sidecar
@@ -40,12 +46,15 @@ Running as a sidecar allows you to directly expose a Kubernetes pod over Tailsca
    ```bash
    curl http://nginx
    ```
+
    Or, if you have [MagicDNS](https://tailscale.com/kb/1081/magicdns/) disabled:
+
    ```bash
    curl "http://$(tailscale ip -4 nginx)"
    ```
 
 #### Userspace Sidecar
+
 You can also run the sidecar in userspace mode. The obvious benefit is reducing the amount of permissions Tailscale needs to run, the downside is that for outbound connectivity from the pod to the Tailnet you would need to use either the [SOCKS proxy](https://tailscale.com/kb/1112/userspace-networking) or HTTP proxy.
 
 1. Create and login to the sample nginx pod with a Tailscale sidecar
@@ -61,23 +70,29 @@ You can also run the sidecar in userspace mode. The obvious benefit is reducing
    ```bash
    curl http://nginx
    ```
+
    Or, if you have [MagicDNS](https://tailscale.com/kb/1081/magicdns/) disabled:
+
    ```bash
    curl "http://$(tailscale ip -4 nginx)"
    ```
 
 ### Sample Proxy
+
 Running a Tailscale proxy allows you to provide inbound connectivity to a Kubernetes Service.
 
 1. Provide the `ClusterIP` of the service you want to reach by either:
 
    **Creating a new deployment**
+
    ```bash
    kubectl create deployment nginx --image nginx
    kubectl expose deployment nginx --port 80
    export TS_DEST_IP="$(kubectl get svc nginx -o=jsonpath='{.spec.clusterIP}')"
    ```
+
    **Using an existing service**
+
    ```bash
    export TS_DEST_IP="$(kubectl get svc <SVC_NAME> -o=jsonpath='{.spec.clusterIP}')"
    ```