CI: avoid ruff warning (#3244)

Avoid this warning:

	warning: `ruff <path>` is deprecated. Use `ruff check <path>` instead.

Author: DimitriPapadopoulos

.github/workflows/contrib.yml

@@ -26,7 +26,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - run: pipx run ruff .
+      - run: pipx run ruff check .
       - run: pipx run ruff format --diff .
 
   codespell: