Support for including artifacts from the previous build

[ffMathy]

It would be great if there was support for downloading the artifacts from the previous build also.

This could be used as a way of storing something per build, for instance data on what test coverage was run, to do test splitting based on timing data, and only run affected tests etc.

I plan on making something for test splitting based on this action, but I need the feature of being able to fetch artifacts from the last build.