Incorrect return type of Model.create

[shwao]

The return type of Model.create is void if the option ignoreDuplicates is true or returning is false.

https://github.com/sequelize/sequelize/blob/56bb1d6ef9827f604d7bcef945abb7e213f2322d/types/lib/model.d.ts#L1982

But the method actually returns an instance.

[shwao]

I force pushed to trigger the checks.