## Issue Addressed
NA
## Proposed Changes
Presently `master` is stable (and will be sunsetted) which means our docs only update after a release. This PR sets the docs to build on the `unstable` branch, which is equivalent to what what we've always had.
## Additional Info
This does raise the question of whether or not docs should target `stable` or `unstable`, but I'd prefer to maintain current functionality and merge #1966 for now. I think having two versions might be handy, one for stable and one for unstable; I don't imagine this very difficult to achieve.
