MAINT Update pre-commit setup for black (scikit-learn#20292)

Author: rth

.pre-commit-config.yaml

@@ -5,14 +5,15 @@ repos:
     -   id: check-yaml
     -   id: end-of-file-fixer
     -   id: trailing-whitespace
+-   repo: https://github.com/psf/black
+    rev: 21.6b0
+    hooks:
+    -   id: black
 -   repo: https://gitlab.com/pycqa/flake8
-    rev: 3.7.8
+    rev: 3.9.2
     hooks:
     -   id: flake8
         types: [file, python]
-        # only check for unused imports for now, as long as
-        # the code is not fully PEP8 compatible
-        args: [--select=F401]
 -   repo: https://github.com/pre-commit/mirrors-mypy
     rev: v0.782
     hooks: