Bump psf/black from 25.9.0 to 25.12.0

Bumps [psf/black](https://github.com/psf/black) from 25.9.0 to 25.12.0.
- [Release notes](https://github.com/psf/black/releases)
- [Changelog](https://github.com/psf/black/blob/main/CHANGES.md)
- [Commits](psf/black@af0ba72...782e560)

---
updated-dependencies:
- dependency-name: psf/black
  dependency-version: 25.12.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

.github/workflows/black.yml

@@ -14,6 +14,6 @@ jobs:
       - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v4
       - name: Set up problem matcher for Black output
         run: echo '::add-matcher::.github/problem-matchers/black.json'
-      - uses: psf/black@af0ba72a73598c76189d6dd1b21d8532255d5942 # stable
+      - uses: psf/black@782e5605c86aab56be6f905da10dcd3e463fd9c2 # stable
         with:
           src: "./unitary"