Adjust versioning scheme

[MoisesGSalas]

This web service is tied to the tutor-contrib-codejail and at the moment it follows the tutor versioning scheme (each major version reflects an openedx release, starting with 10->Juniper).

The main problem is that each tag in the tutor plugins must hava a mirror in the codejailservice repository, because that's how code for the image is retrieved.

I propose instead that we use something more akin to the way tutor plugins and IDAs map. IDAs (like edx_notes_api, cs_comments_service) use the open-release/<release-name>.<tag-number> for versioning and their plugins keep an additional variable that points to the open-release tag while retaining the tutor versioning system.

I think the redwood upgrade is a good opportunity for this. We can probably start using release/redwood.1 taking into account the renaming of release branches for sumac (see: Should we rename the release branches?)

[MaferMazu]

Thank you for this proposal, @MoisesGSalas. I have experienced issues with this plugin mirror versioning before, and your proposal sounds good. I agree with this proposal and using release/.

This solves eduNEXT/tutor-contrib-codejail#51

[MoisesGSalas]

I went ahead an tagged the latest commit with the release/redwood.1 tag. I also created a branch redwood to somewhat mimic the same process as other openedx IDAs.

I also released the v18.0.0 of tutor-contrib-codejail.