Bump pylint from 2.9.5 to 2.9.6

Bumps [pylint](https://github.com/PyCQA/pylint) from 2.9.5 to 2.9.6.
- [Release notes](https://github.com/PyCQA/pylint/releases)
- [Changelog](https://github.com/PyCQA/pylint/blob/main/ChangeLog)
- [Commits](pylint-dev/pylint@v2.9.5...v2.9.6)

---
updated-dependencies:
- dependency-name: pylint
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

requirements-ci.txt

@@ -5,7 +5,7 @@ coveralls==3.2.0
 mypy==0.910
 pydocstyle==6.1.1
 flake8==3.9.2
-pylint==2.9.5
+pylint==2.9.6
 black==21.7b0
 treon==0.1.3
 maggma==0.29.0