Bump pylint from 2.7.4 to 2.12.2 (#1137)

Author: dependabot[bot]

requirements/requirements_dev.txt

@@ -10,7 +10,7 @@ hypothesis==6.8.9
 invoke==1.6.0
 placebo==0.10.0
 pre-commit==2.16.0
-pylint==2.7.4
+pylint==2.12.2
 pytest==6.2.5
 pytest-black==0.3.12
 pytest-cov==3.0.0