TL:DR: Yes.
One way to think about it is this... if the project license allows for others to take the content and host it on a service like readthedocs, then project committers can too.
readthedocs is an external resource and so, if it's used an official means of distributing project content, then the project team needs to make sure that the keys are shared by more than one committer (there's more in the
handbook), and care must be taken to leverage that external resource in an open, transparent, and vendor neutral manner.
I know that this isn't the question that you asked, but... As I said on the incubation list, documentation is a core project resource and so the source should be managed along with the code (ideally in a EF-managed Git repository). Documentation is a resource that adopters, contributors, and the community in general needs to have access to under the same set of rules as the project code. Whether or not a tutorial qualifies as documentation is something that the project team needs to determine (with help, if needed, from the PMC).
HTH,
Wayne