standalone tests should all use new `standaloneTest` function

[davepacheco]

#101 added a common mechanism to run the standalone tests to replace the boilerplate dozens of lines of code that the tests are using today. That change only refactored one of the tests -- there are still several that are doing their own ad hoc stuff that's done more consistently and robustly by the new function. We should refactor these to use the new function.