chore(deps): update dependency black to v26 (#4422)

Author: renovate-bot

.github/workflows/linter/requirements.txt

@@ -2,7 +2,7 @@ git+https://github.com/tensorflow/docs
 ipython
 jupyter
 nbconvert
-black==25.12.0
+black==26.1.0
 pyupgrade==3.21.2
 isort==7.0.0
 flake8==7.3.0