Merge #76

76: Update astroid to 2.5.7 r=aragilar a=pyup-bot


This PR updates [astroid](https://pypi.org/project/astroid) from **2.5.6** to **2.5.7**.



<details>
  <summary>Changelog</summary>
  
  
   ### 2.5.7
   ```
   ============================
Release Date: 2021-05-09

* Fix six.with_metaclass transformation so it doesn&#39;t break user defined transformations.

* Fix detection of relative imports.
  Closes 930
  Closes PyCQA/pylint4186

* Fix inference of instance attributes defined in base classes

  Closes 932

* Update `infer_named_tuple` brain to reject namedtuple definitions
  that would raise ValueError

  Closes 920

* Do not set instance attributes on builtin object()

 Closes 945
 Closes PyCQA/pylint4232
 Closes PyCQA/pylint4221
 Closes PyCQA/pylint3970
 Closes PyCQA/pylint3595

* Fix some spurious cycles detected in ``context.path`` leading to more cases
  that can now be inferred

  Closes 926

* Add ``kind`` field to ``Const`` nodes, matching the structure of the built-in ast Const.
  The kind field is &quot;u&quot; if the literal is a u-prefixed string, and ``None`` otherwise.

  Closes 898

* Fix property inference in class contexts for properties defined on the metaclass

  Closes 940

* Update enum brain to fix definition of __members__ for subclass-defined Enums

  Closes PyCQA/pylint3535
  Closes PyCQA/pylint4358

* Update random brain to fix a crash with inference of some sequence elements

  Closes 922

* Fix inference of attributes defined in a base class that is an inner class

  Closes 904

* Allow inferring a return value of None for non-abstract empty functions and
  functions with no return statements (implicitly returning None)

  Closes 485

* scm_setuptools has been added to the packaging.

* Astroid&#39;s tags are now the standard form ``vX.Y.Z`` and not ``astroid-X.Y.Z`` anymore.

* Add initial support for Pattern Matching in Python 3.10
   ```
   
  
</details>


 

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



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

pylint-requirements.txt

@@ -1,2 +1,2 @@
-astroid==2.5.6
+astroid==2.5.7
 pylint==2.8.2