Account for windows path separators in tests

Author: abravalheri

setuptools/tests/test_sdist.py

@@ -458,7 +458,7 @@ def test_exclude_dev_only_cache_folders(self, source_dir):
 
         cmd = self.setup_with_extension()
         self.assert_package_data_in_manifest(cmd)
-        manifest = cmd.filelist.files
+        manifest = {f.replace(os.sep, '/') for f in cmd.filelist.files}
         for path in excluded:
             assert os.path.exists(path)
             assert path not in manifest, (path, manifest)