Bump pylint from 2.2.2 to 2.3.0

Bumps [pylint](https://github.com/PyCQA/pylint) from 2.2.2 to 2.3.0.
- [Release notes](https://github.com/PyCQA/pylint/releases)
- [Changelog](https://github.com/PyCQA/pylint/blob/master/ChangeLog)
- [Commits](pylint-dev/pylint@pylint-2.2.2...pylint-2.3.0)

Signed-off-by: dependabot[bot] <support@dependabot.com>

test-requirements.txt

@@ -5,7 +5,7 @@
 #    pip-compile --output-file test-requirements.txt test-requirements.in
 #
 asn1crypto==0.24.0        # via cryptography
-astroid==2.1.0            # via pylint
+astroid==2.2.0            # via pylint
 async-generator==1.10
 atomicwrites==1.3.0       # via pytest
 attrs==18.2.0
@@ -38,7 +38,7 @@ pycodestyle==2.5.0        # via flake8
 pycparser==2.19           # via cffi
 pyflakes==2.1.0           # via flake8
 pygments==2.3.1           # via ipython
-pylint==2.2.2
+pylint==2.3.0
 pyopenssl==19.0.0
 pytest-cov==2.6.1
 pytest-faulthandler==1.5.0