[Feature request] [Active record] - Add order option to "find_in_batches" and "find_each"

[佑馬光吉]

Currently, if "primary_key" does not exist, "find_in_batches" and "find_each" will result in an error.

Since there may be cases where "primary_key" does not exist when performing batch processing,

I think that it can be solved by adding an order option.