`Bluebird.each` and `Bluebird.mapSeries` will accept a callback with `value` parameter,
the `value` should be the item in the array, not array itself.
For example:
```
const arr = [1, 2];
Bluebird.each(arr, function(value, idx) {
console.log(`value: ${value}, idx: ${idx}`);
})
```
the output will be
```
value: 1, idx: 0
value: 2, idx: 1
```
This PR fix the test cases for `each` and `mapSeries` APIs.
PR Close#36295