docs: attachedRoutes comment updated

The go comment for the Gateway's AttachedRoutes field has been updated
by adding the condition that the Routes need to be accepted to be
considered successfully attached to a listener.

Signed-off-by: Mattia Lavacca <lavacca.mattia@gmail.com>

Author: mlavacca

apis/v1beta1/gateway_types.go

@@ -674,7 +674,7 @@ type ListenerStatus struct {
 	// +kubebuilder:validation:MaxItems=8
 	SupportedKinds []RouteGroupKind `json:"supportedKinds"`
 
-	// AttachedRoutes represents the total number of Routes that have been
+	// AttachedRoutes represents the total number of accepted Routes that have been
 	// successfully attached to this Listener.
 	AttachedRoutes int32 `json:"attachedRoutes"`