Coerce new `TaskState.nbytes` value to `int` (#4311)
Coerce new `TaskState.nbytes` value to `int` (#4311)

Make sure that whatever value we assign to `nbytes` is an `int`. This is
important as `Schedule.bandwidth` may be a `float`. So the value here
could be a `float`. Though we only measure `nbytes` in whole values.
dask/distributed,dask/distributed,dask/distributed,dask/distributed