Adds middlewares examples for k8s.

docs/content/middlewares/addprefix.md

@@ -12,17 +12,18 @@ The AddPrefix middleware updates the URL Path of the request before forwarding i
 ```yaml tab="Docker"
 # Prefixing with /foo
 labels:
-- "traefik.http.middlewares.add-bar.addprefix.prefix=/foo"
+- "traefik.http.middlewares.add-foo.addprefix.prefix=/foo"
 ```
 
 ```yaml tab="Kubernetes"
+# Prefixing with /foo
 apiVersion: traefik.containo.us/v1alpha1
 kind: Middleware
 metadata:
-  name: addprefix
+  name: add-foo
 spec:
-  addprefix:
-    prefix: /bar
+  addPrefix:
+    prefix: /foo
 ```
 
 ```toml tab="File"
@@ -34,6 +35,6 @@ spec:
 
 ## Configuration Options
 
-### prefix
+### `prefix`
 
 `prefix` is the string to add before the current path in the requested URL. It should include the leading slash (`/`).