Pydantic-odm

- Bugfix: serializing to json on a BaseDBMixin with child DBPydanticMixin's fails. PR 34 by dhensen

- Summary grammar fix. PR 28 by languitar
- Skip setuptools 50.0 because of a pip/setuptools related issue. PR 32 by dhensen
- Fix project formatters. PR 33 by i8enn
- Fix BaseMongoDBDecoder for documents with arrays of simple type. PR 30 by antipooh
- Add MongoDB encoder: Decimal to Decimal128. PR 31 by dhensen
- Add passing in optional parameters of AsyncIOMotorClient. PR 29 by dhensen

- Fix missing nested packages in build by i8enn

- Created MongoDB encoders for encode queries or model to MongoDB driver. PR 24 by i8enn
- Fix creating empty `id` field in models. Fix issue 23. PR 25 by i8enn
- Created MongoDB decoders. PR 25 by i8enn
- Changed pytest and coverage configuration. PR 25 by i8enn

* Implemented `id` public property for `PydanticDBMixin`. Updated *db mixins* and their tests. PR 17 by i8enn
* Implemented Enum support. PR 20 by i8enn
* Replaces package manager from Pipenv to Poetry. PR 21 by i8enn

* Fix arguments type in `update_many` method from `PydanticDBMixin`. PR 16 by i8enn