[pre-commit.ci] pre-commit autoupdate (#424)

updates:
- [github.com/adamchainz/blacken-docs: 1.19.1 → 1.20.0](adamchainz/blacken-docs@1.19.1...1.20.0)

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

@@ -41,7 +41,7 @@ repos:
         types_or: [yaml, markdown, html, css, javascript, json]
 
   - repo: https://github.com/adamchainz/blacken-docs
-    rev: 1.19.1
+    rev: 1.20.0
     hooks:
       - id: blacken-docs
         additional_dependencies: [black~=25.0]