Update factory_boy to 2.8.1

[pyup-bot]

There's a new version of factory_boy available.
You are currently using 2.7.0. I have updated it to 2.8.1

These links might come in handy: PyPI | Changelog | Repo

Changelog

2.8.1

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Bugfix:

• Fix packaging issues.

2.8.0

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New:

• :issue:240: Call post-generation declarations in the order they were declared,
  thanks to Oleg Pidsadnyi <https://github.com/olegpidsadnyi>_.
• :issue:309: Provide new options for SQLAlchemy session persistence

Bugfix:

• :issue:334: Adjust for the package change in faker

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖

[codecov-io]

Codecov Report

Merging #275 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##           master   #275   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           5      5           
  Lines          64     64           
=====================================
  Hits           64     64

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[pyup-bot]

Closing this in favor of #282