[pre-commit.ci] pre-commit autoupdate (#315)

updates:
- [github.com/akaihola/darker: 1.7.3 → v2.0.0](akaihola/darker@1.7.3...v2.0.0)

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

.pre-commit-config.yaml

@@ -31,7 +31,7 @@ repos:
     hooks:
       - id: isort
   - repo: https://github.com/akaihola/darker
-    rev: 1.7.3
+    rev: v2.0.0
     hooks:
       - id: darker
         additional_dependencies: [black]