PYTHON-3531 Pre-commit failure due to flake8 repository move (#1122)

Author: blink1073

.pre-commit-config.yaml

@@ -30,7 +30,7 @@ repos:
     files: \.py$
     args: [--profile=black]
 
-- repo: https://gitlab.com/pycqa/flake8
+- repo: https://github.com/PyCQA/flake8
   rev: 3.9.2
   hooks:
   - id: flake8