Allow linking to the latest documentation with the specific version

This is more of a "hosting the documentation" kind of issue, and might not be the right place for it. But thought to report it here anyway, since it seems to affect just Barman cloud plugin and I couldn't figure out a better place for it.

Currently it isn't possible to link to the latest plugin version documentation with a version specific link. I.e.
- works
- does not work
- works

This means that when writing documentation like "here's the list of relevant documentation on different software we're using", one can't link to the correct version. Which leads to documentation like "remember to double check that the documentation version matches the version on the list!".

No se nombra ningún archivo, prueba ni punto de entrada. Empieza reproduciendo las URL de documentación que funcionan y las que fallan, y localizando la configuración de hosting de la documentación versionada del plugin Barman Cloud. Se considera completado cuando la versión más reciente del plugin, incluida la 0.9.0, es accesible mediante un enlace de documentación específico de la versión.

Escrito por el modelo de indexación a partir del texto del issue.