build(deps): Bump black from 25.11.0 to 26.3.1 in /dev

Bumps [black](https://github.com/psf/black) from 25.11.0 to 26.3.1.
- [Release notes](https://github.com/psf/black/releases)
- [Changelog](https://github.com/psf/black/blob/main/CHANGES.md)
- [Commits](psf/black@25.11.0...26.3.1)

---
updated-dependencies:
- dependency-name: black
  dependency-version: 26.3.1
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

dev/pyproject.toml

@@ -9,7 +9,7 @@ description = "Tools for developers."
 license = "Apache-2.0"
 authors = [{ name = "The Flower Authors", email = "hello@flower.ai" }]
 requires-python = ">=3.10"
-dependencies = ["black==25.11.0", "PyYAML>=6.0.2,<7.0.0"]
+dependencies = ["black==26.3.1", "PyYAML>=6.0.2,<7.0.0"]
 
 [dependency-groups]
 dev = [