Update pylint to 2.4.2

[pyup-bot]

This PR updates pylint from 2.4.1 to 2.4.2.

Changelog

2.4.2

===========================

Release date: 2019-09-30


* ``ignored-modules`` can skip submodules. Close 3135

* ``self-assigning-variable`` skips class level assignments.

Close 2930

* ``consider-using-sys-exit`` is exempted when `exit()` is imported from `sys`

Close 3145

* Exempt annotated assignments without variable from ``class-variable-slots-conflict``

Close 3141

* Fix ``utils.is_error`` to account for functions returning early.

This fixes a false negative with ``unused-variable`` which was no longer triggered
when a function raised an exception as the last instruction, but the body of the function
still had unused variables.

Close 3028

Links

• PyPI: https://pypi.org/project/pylint
• Changelog: https://pyup.io/changelogs/pylint/
• Repo: https://github.com/PyCQA/pylint