[pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/keewis/blackdoc: v0.3.9 → v0.4.0](keewis/blackdoc@v0.3.9...v0.4.0)

Author: pre-commit-ci[bot]

.pre-commit-config.yaml

@@ -34,7 +34,7 @@ repos:
     language_version: python3
 
 - repo: https://github.com/keewis/blackdoc
-  rev: v0.3.9
+  rev: v0.4.0
   hooks:
     - id: blackdoc