Update CONTRIBUTING.md

CONTRIBUTING.md

@@ -21,7 +21,7 @@ pip install pre-commit
 pre-commit install
 ```
 
-These hooks use Black and isort to format the code, and flake8 to lint it.
+These hooks use ruff to lint and format the code.
 
 Now make your changes. Make sure to include additional tests if necessary.
 
@@ -40,16 +40,3 @@ git push
 ```
 
 Finally, open a pull request on GitHub!
-
-## Contributor License Agreement
-
-Contributions to this project must be accompanied by a Contributor License
-Agreement (CLA). You (or your employer) retain the copyright to your
-contribution; this simply gives us permission to use and redistribute your
-contributions as part of the project. Head over to
-<https://cla.developers.google.com/> to see your current agreements on file or
-to sign a new one.
-
-You generally only need to submit a CLA once, so if you've already submitted one
-(even if it was for a different project), you probably don't need to do it
-again.