Update Codecov token application

Signed-off-by: Beat Buesser <[email protected]>

Author: beat-buesser

.github/workflows/ci-scikit-learn.yml

@@ -57,6 +57,7 @@ jobs:
         run: ./run_tests.sh ${{ matrix.framework }}
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v4
+        env:
+          CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
         with:
           fail_ci_if_error: true
-          token: ${{ secrets.CODECOV_TOKEN }}