🐛Ensure the default $PATH value is pre-loaded

This patch imports the system-global profile script to
populate the `$PATH` variable with the typically available binary
paths.

Ref:
https://github.com/pypa/gh-action-pypi-publish/issues/112#issuecomment-1340065840

.github/workflows/self-smoke-test-action.yml

@@ -84,6 +84,8 @@ jobs:
           }}/public/
     - name: ✅ Smoke-test the locally checked out action
       uses: ./test
+      env:
+        PATH: utter-nonsense
       with:
         user: ${{ env.devpi-username }}
         password: ${{ env.devpi-password }}