[pre-commit.ci] pre-commit autoupdate (#339)

updates:
- [github.com/psf/black: 21.6b0 → 21.7b0](psf/black@21.6b0...21.7b0)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: pre-commit-ci[bot]

.pre-commit-config.yaml

@@ -11,7 +11,7 @@ repos:
   - id: end-of-file-fixer
   - id: trailing-whitespace
 - repo: https://github.com/psf/black
-  rev: 21.6b0
+  rev: 21.7b0
   hooks:
   - id: black
     language_version: python3