wait(condition) while running an @async task can not be interrupted by ctrl-c

[tehrengruber]

Consider the following 2 scenarios

Scenario 1

cond = Condition()
wait(cond)

# press ctrl-c
#^CERROR: InterruptException:

Scenario 2

cond = Condition()

@async begin
    while true
        sleep(1)
        println(1)
    end
end

wait(cond)

# press ctrl-c
#^CERROR (unhandled task failure): InterruptException:
#^CERROR (unhandled task failure): InterruptException:
# ...

Now in scenario 1 pressing ctrl-c just interrupts the wait call und you get back to the prompt and everthings fine

But in scenario 2 pressing ctrl-c actually interrupts the task and not the wait call. Which is not correct I guess and even worse after the task was interrupted you are stuck and you won't get back to the prompt.

[JeffBezanson]

I believe I fixed this in #10416, and it regressed.

[tkelman]

any reasonable way of testing for this?

[tkelman]

backported in #13107