pre-commit: autoupdate hook versions (#103)

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

Author: github-actions[bot]

.pre-commit-config.yaml

@@ -1,7 +1,7 @@
 # https://pre-commit.com/
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v3.4.0
+    rev: v4.0.0
     hooks:
       - id: trailing-whitespace
       - id: end-of-file-fixer
@@ -14,7 +14,7 @@ repos:
       - id: isort
   # https://github.com/python/black#version-control-integration
   - repo: https://github.com/python/black
-    rev: 21.5b0
+    rev: 21.5b1
     hooks:
       - id: black
   - repo: https://github.com/keewis/blackdoc