Bump pylint from 2.7.3 to 2.7.4

Bumps [pylint](https://github.com/PyCQA/pylint) from 2.7.3 to 2.7.4.
- [Release notes](https://github.com/PyCQA/pylint/releases)
- [Changelog](https://github.com/PyCQA/pylint/blob/master/ChangeLog)
- [Commits](pylint-dev/pylint@pylint-2.7.3...pylint-2.7.4)

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

requirements-lint.txt

@@ -1,7 +1,7 @@
 # linters
 pycodestyle==2.7.0
 pydocstyle==6.0.0
-pylint==2.7.3
+pylint==2.7.4
 pygments
 pyroma==3.1
 -r requirements-test.txt