[pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/psf/black: 21.4b2 → 21.5b1](psf/black@21.4b2...21.5b1)

Author: pre-commit-ci[bot]

.pre-commit-config.yaml

@@ -6,7 +6,7 @@ repos:
     - id: end-of-file-fixer
     - id: trailing-whitespace
 - repo: https://github.com/psf/black
-  rev: 21.4b2
+  rev: 21.5b1
   hooks:
     - id: black
       args: [--line-length=80]