After https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/12566
most route helpers methods do not need to take project.namespace as a
parameter and should be enogh to pass only project.

Removing the need to pass project.namespace helps to reduce some cases
where N+1 is generated due to project.namespace.becomes(Namespace)
creating a new instance of the namepsace thus not making use of
eager loaded associations