[Core] Fix test_runtime_env_working_dir_4 for Windows (#47505)

Windows path needs to be escaped.

Signed-off-by: Jiajun Yao <[email protected]>

Author: jjyao

python/ray/tests/test_runtime_env_working_dir_4.py

@@ -213,9 +213,11 @@ def test_two_concurrent_jobs_with_same_working_dir(call_ray_start, tmp_working_d
     https://github.com/ray-project/ray/issues/47471
     """
 
+    # Windows path has backslash so we need to escape it
+    tmp_working_dir = tmp_working_dir.encode("unicode_escape").decode()
     script = f"""
 import ray
-ray.init(runtime_env={{"working_dir": "{str(tmp_working_dir)}"}})
+ray.init(runtime_env={{"working_dir": "{tmp_working_dir}"}})
 """
     job1 = run_string_as_driver_nonblocking(script)
     job2 = run_string_as_driver_nonblocking(script)