Merge #142

142: Update pytest-cov to 2.9.0 r=YourLocalBlake a=pyup-bot


This PR updates [pytest-cov](https://pypi.org/project/pytest-cov) from **2.8.1** to **2.9.0**.



<details>
  <summary>Changelog</summary>
  
  
   ### 2.9.0
   ```
   ------------------

* Fixed ``RemovedInPytest4Warning`` when using Pytest 3.10.
  Contributed by Michael Manganiello in `354 &lt;https://github.com/pytest-dev/pytest-cov/pull/354&gt;`_.
* Made pytest startup faster when plugin not active by lazy-importing.
  Contributed by Anders Hovmöller in `339 &lt;https://github.com/pytest-dev/pytest-cov/pull/339&gt;`_.
* Various CI improvements.
  Contributed by Daniel Hahler in `363 &lt;https://github.com/pytest-dev/pytest-cov/pull/&gt;`_ and
  `364 &lt;https://github.com/pytest-dev/pytest-cov/pull/364&gt;`_.
* Various Python support updates (drop EOL 3.4, test against 3.8 final).
  Contributed by Hugo van Kemenade in
  `336 &lt;https://github.com/pytest-dev/pytest-cov/pull/336&gt;`_ and
  `367 &lt;https://github.com/pytest-dev/pytest-cov/pull/367&gt;`_.
* Changed ``--cov-append`` to always enable ``data_suffix`` (a coverage setting).
  Contributed by Harm Geerts in
  `387 &lt;https://github.com/pytest-dev/pytest-cov/pull/387&gt;`_.
* Changed ``--cov-append`` to handle loading previous data better
  (fixes various path aliasing issues).
* Various other testing improvements, github issue templates, example updates.
* Fixed internal failures that are caused by tests that change the current working directory by
  ensuring a consistent working directory when coverage is called.
  See `306 &lt;https://github.com/pytest-dev/pytest-cov/issues/306&gt;`_ and
  `coveragepy881 &lt;https://github.com/nedbat/coveragepy/issues/881&gt;`_
   ```
   
  
</details>


 

<details>
  <summary>Links</summary>
  
  - PyPI: https://pypi.org/project/pytest-cov
  - Changelog: https://pyup.io/changelogs/pytest-cov/
  - Repo: https://github.com/pytest-dev/pytest-cov
</details>



Co-authored-by: pyup-bot <github-bot@pyup.io>

test-requirements.txt

@@ -1,5 +1,5 @@
 pytest==5.4.1;python_version>'3.0'
-pytest-cov==2.8.1
+pytest-cov==2.9.0
 #pytest-datadir
 #pytest-mpl
 #pytest-regtest