Fix route attachments to gateways

Co-authored-by: Romain <rtribotte@users.noreply.github.com>

pkg/provider/kubernetes/gateway/fixtures/httproute/simple_with_bad_rule.yml

@@ -1,46 +0,0 @@
----
-kind: GatewayClass
-apiVersion: gateway.networking.k8s.io/v1
-metadata:
-  name: my-gateway-class
-spec:
-  controllerName: traefik.io/gateway-controller
-
----
-kind: Gateway
-apiVersion: gateway.networking.k8s.io/v1
-metadata:
-  name: my-gateway
-  namespace: default
-spec:
-  gatewayClassName: my-gateway-class
-  listeners: # Use GatewayClass defaults for listener definition.
-    - name: http
-      protocol: HTTP
-      port: 80
-      allowedRoutes:
-        namespaces:
-          from: Same
-
----
-kind: HTTPRoute
-apiVersion: gateway.networking.k8s.io/v1
-metadata:
-  name: http-app-1
-  namespace: default
-spec:
-  parentRefs:
-    - name: my-gateway
-      kind: Gateway
-      group: gateway.networking.k8s.io
-  hostnames:
-    - "foo.com"
-  rules:
-    - matches:
-        - path:
-            type: Unsupported
-            value: /bar
-      backendRefs:
-        - name: whoami
-          port: 80
-          weight: 1