Fix filters for mongoengine, peewee and pymongo

In #703 the `BaseModelView` updated the filters to a 3 items tuple.
Diff reference:
https://github.com/mrjoes/flask-admin/commit/9606f2099b714944bb5f3b830261e876a29ce311#diff-401640c72e6a6b2a48e711090af0534cL1116

This pull request propagates the expected value to mongoengine, peewee and pymongo `BaseView.get_list()`.