BLD/CI: Merge linting commands into one command

Author: Kai-Striega

.github/workflows/pythonpackage.yml

@@ -32,9 +32,7 @@ jobs:
         # Tell us what version we are using
         ruff version
         # Check the source file, ignore type annotations (ANN) for now.
-        ruff check numpy_financial/ --ignore F403 --select E,F,B,I
-        # Check the test and benchmark files
-        ruff check tests/ benchmarks/ --select E,F,B,I
+        ruff check numpy_financial/ benchmarks/ --ignore F403 --select E,F,B,I
     - name: Build project
       run: |
         spin build -v