Update CONTRIBUTING.md (#1046)

Author: hotzenklotz

CONTRIBUTING.md

@@ -115,8 +115,8 @@ See below for specifics of the different packages. Let's have a look at the comm
   To install the dependencies for all sub-projects, run `make install`.
 
 * **Tooling** we use across the sub-projects to enforce coding styles and tests:
-    * `./format.sh`: black and isort
-    * `./lint.sh`: pylint
+    * `./format.sh`: ruff
+    * `./lint.sh`: ruff
     * `./typecheck.sh`: mypy
     * `./test.sh`: pytest and custom scripts