Update gateway api provider to v1alpha2

Co-authored-by: Tom Moulard <tom.moulard@traefik.io>

docs/content/reference/dynamic-configuration/kubernetes-gateway-traefik-lb-svc.yml

@@ -5,8 +5,8 @@ metadata:
   name: traefik-controller
 
 ---
-kind: Deployment
 apiVersion: apps/v1
+kind: Deployment
 metadata:
   name: traefik
 
@@ -15,24 +15,27 @@ spec:
   selector:
     matchLabels:
       app: traefik-lb
+
   template:
     metadata:
       labels:
         app: traefik-lb
+
     spec:
       serviceAccountName: traefik-controller
       containers:
         - name: traefik
-          image: traefik/traefik:latest
-          imagePullPolicy: IfNotPresent
+          image: traefik:v2.5
           args:
             - --entrypoints.web.address=:80
             - --entrypoints.websecure.address=:443
             - --experimental.kubernetesgateway
             - --providers.kubernetesgateway
+
           ports:
             - name: web
               containerPort: 80
+
             - name: websecure
               containerPort: 443
 
@@ -41,16 +44,19 @@ apiVersion: v1
 kind: Service
 metadata:
   name: traefik
+
 spec:
+  type: LoadBalancer
   selector:
     app: traefik-lb
+
   ports:
     - protocol: TCP
       port: 80
       targetPort: web
       name: web
+
     - protocol: TCP
       port: 443
       targetPort: websecure
       name: websecure
-  type: LoadBalancer