As a platform engineer I want to be able to delete versions from the history of the building block definition. When using dependencies it is virtually impossible to roll back a dependency. This leads to a situation where I cannot delete an output variable because it was once used in an old version of a building block definition. If no building block is using the output variable anymore I want to be able to delete it. This would be made possible by deleting the old version that still had the dependency. Another option would be to issue a warning, that deleting the variable might break older building blocks.