Try hashFiles on setup.py

Looking to fix a weird error on macos-14 GitHub Actions runners

Author: simonw

.github/workflows/test.yml

@@ -24,7 +24,7 @@ jobs:
       name: Configure pip caching
       with:
         path: ~/.cache/pip
-        key: ${{ runner.os }}-pip-${{ hashFiles('**/setup.py') }}
+        key: ${{ runner.os }}-pip-${{ hashFiles('setup.py') }}
         restore-keys: |
           ${{ runner.os }}-pip-
     - name: Install dependencies