Update action execution output controller to also close the stream in case execution is paused.
Update action execution output controller to also close the stream in
case execution is paused.

This way we avoid potentially a very long open connection in case
execution is paused for a long time.

It's up to the user to hit the API endpoint again once the execution
resumes.

nzlosh/st2,StackStorm/st2,StackStorm/st2,StackStorm/st2,Plexxi/st2,Plexxi/st2,nzlosh/st2,nzlosh/st2,nzlosh/st2,StackStorm/st2,Plexxi/st2,Plexxi/st2