Update pytest-mock to 1.6.0

[pyup-bot]

There's a new version of pytest-mock available.
You are currently using 1.5.0. I have updated it to 1.6.0

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

Changelog

1.6.0

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• The original assertions raised by the various Mock.assert_* methods
  now appear in the failure message, in addition to the message obtained from
  pytest introspection.
  Thanks quodlibetor_ for the initial patch (79_).

.. _quodlibetor: https://github.com/quodlibetor

.. _79: pytest-dev/pytest-mock#79

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

Happy merging! 🤖

[codecov]

Codecov Report

Merging #25 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##           master    #25   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           9      9           
  Lines         630    630           
  Branches       66     66           
=====================================
  Hits          630    630

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