is isHTTPRouteFilterReferencingSecret too eager ?

*Description*:
i found a weird piece of code when browing candidly

```go
func (r *gatewayAPIReconciler) isHTTPRouteFilterReferencingSecret(nsName *types.NamespacedName) bool {
routeFilterList := &egv1a1.HTTPRouteFilterList{}
if err := r.client.List(context.Background(), routeFilterList, &client.ListOptions{
FieldSelector: fields.OneTermEqualSelector(secretHTTPRouteFilterIndex, nsName.String()),
}); err != nil {
r.log.Error(err, "unable to find associated HTTPRouteFilter")
return false
}

if len(routeFilterList.Items) > 0 {
return true
}

return true
}
```
the filter always return true, wouldn't that cause the filter to be a bit too eager ?

Locate isHTTPRouteFilterReferencingSecret in the Go gateway API reconciler and inspect its callers and nearby tests. Verify the intended result for an empty HTTPRouteFilterList, add coverage for both empty and non-empty results, and run the relevant Go tests.

Written by the indexing model from the issue text.