testsuite: Skip tests for JS backend
JS backend uses its own RTS, so any program which relies on the native RTS will always fail unless explicitly supported by the JS RTS.
This is the second such MR after (!20 (closed)). I had to reopen it and delete my old fork because it inherited master
as a protected branch which prevents force-push
ing and rebasing. Thus I couldn't implement sylvain's suggestion.
Edited by jeffrey young