When a DSL method gets called (e.g. compilerComplicanceLevel), ideally we would call extension.workspaceProp() or extension.addSetupAction() right there, immediately.  That keeps everything local, so there are fewer places to debug.

There are cases, such as installedJres, where you have aggregate several calls to a method into a single action.  In that case, we can use the `close()` method to know that the user has finished calling methods, and we can now take our aggregated actions.