product/hooks: hooks service no longer requires channels service start (#21861)

app/channels.go

@@ -325,10 +325,6 @@ type hooksService struct {
 }
 
 func (s *hooksService) RegisterHooks(productID string, hooks any) error {
-	if s.ch.pluginsEnvironment == nil {
-		return errors.New("could not find plugins environment")
-	}
-
 	return s.ch.srv.hooksManager.AddProduct(productID, hooks)
 }