There are basically two ways to get this. Manually importing it (link to Github in first post) or by using the Hubitat Package Manager. Package Manager is nice because once you get the app installed, it is much easier to search for new community based apps and drivers, and it simplifies installing and updating things, especially something like Echo Speaks where there are multiple apps and drivers needed for one (main) application.
Again, you will have to import this Github raw link into the Apps Code section of Hubitat, but once you do that, it is fairly straightforward from there.
