Fix RayCodeGen

Signed-off-by: Aylei <[email protected]>

Author: aylei

sky/backends/cloud_vm_ray_backend.py

@@ -302,6 +302,8 @@ def add_prologue(self, job_id: int) -> None:
             from sky.skylet import autostop_lib
             from sky.skylet import constants
             from sky.skylet import job_lib
+            from sky.utils import context
+            from sky.utils import context_utils
             from sky.utils import log_utils
             from sky.utils import subprocess_utils