Test for GH 2684 (questions)

[Altai-man]

There are a couple of things I am not really sure about in this test, can someone, please, answer the following?

1)Description of make-tmp-dir says that the end-user must clean up created files beforehand, see https://github.com/perl6/roast/issues/384 ticket. But the previous test in this file does not seem to do any cleanup, so I didn't add it too. Should both tests be fixed? Or maybe we have to do something with the ticket? If yes, how can I help? To change rmdir into rm -rf equivalent and run spectest seeing if anything broke? 2)It seems that this issue did not end up in a release... I tried the test on both 2018.12 and 2019.03 and it just passes... But ultimately I am not sure if it passes because the test is correct and the bug is fixed already(and on 2018.12 it was not yet introduced) or it is just a broken test. Possibly I can roll back to the commit before the fix, but what to do with two dependent repos, moarvm and nqp, just search their respective commits of that time?

Issue link -> https://github.com/rakudo/rakudo/issues/2684