when multiple NProgress.set/.inc updates are queued, make sure they zip through very quickly: when these are queued it always means several places in the same code (execution run) invoked these NProgress APIs and when that happens only the last one really matters (apart from the message text which *may* have been updated by any of the 'older' calls, hence we keep them all, execute them all (in order) but still make sure they execute relatively quickly).