test: adjust fspath test for windows

Author: ap--

upath/tests/test_core.py

@@ -255,15 +255,17 @@ def test_compare_to_pathlib_path_ne():
     assert pathlib.Path("/bucket/folder") == UPath("/bucket/folder")
 
 
-def test_handle_fspath_args():
+def test_handle_fspath_args(tmp_path):
+    f = os.fspath(tmp_path.joinpath("file.txt"))
+
     class X:
         def __str__(self):
             raise ValueError("should not be called")
 
         def __fspath__(self):
-            return "/some/path"
+            return f
 
-    assert UPath(X()).path == "/some/path"
+    assert UPath(X()).path == f
 
 
 @pytest.mark.parametrize(