[Jobs] Hide dashboard from Job Submission import path (#22223)

For public SDK APIs, change the import path from 

```python
from ray.dashboard.modules.job.common import JobStatus, JobStatusInfo
from ray.dashboard.modules.job.sdk import JobSubmissionClient
```

to 
```python
from ray.job_submission import JobStatus, JobSubmissionClient
```

`JobStatus`, `JobStatusInfo` and `JobSubmissionClient` were the only names referenced in the SDK doc so far, but we can add more later as they appear.

dashboard/modules/job/cli.py

@@ -9,8 +9,7 @@ import yaml
 import click
 
 from ray.autoscaler._private.cli_logger import add_click_logging_options, cli_logger, cf
-from ray.dashboard.modules.job.common import JobStatus
-from ray.dashboard.modules.job.sdk import JobSubmissionClient
+from ray.job_submission import JobStatus, JobSubmissionClient
 
 
 def _get_sdk_client(

dashboard/modules/job/job_manager.py

@@ -14,9 +14,8 @@ import ray
 from ray.exceptions import RuntimeEnvSetupError
 import ray.ray_constants as ray_constants
 from ray.actor import ActorHandle
+from ray.job_submission import JobStatus, JobStatusInfo
 from ray.dashboard.modules.job.common import (
-    JobStatus,
-    JobStatusInfo,
     JobStatusStorageClient,
     JOB_ID_METADATA_KEY,
     JOB_NAME_METADATA_KEY,

dashboard/modules/job/tests/test_http_job_server.py

@@ -8,10 +8,10 @@ import pytest
 from unittest.mock import patch
 
 import ray
-from ray.dashboard.modules.job.common import CURRENT_VERSION, JobStatus
+from ray.job_submission import JobSubmissionClient, JobStatus
+from ray.dashboard.modules.job.common import CURRENT_VERSION
 from ray.dashboard.modules.job.sdk import (
     ClusterInfo,
-    JobSubmissionClient,
     parse_cluster_info,
 )
 from ray.dashboard.tests.conftest import *  # noqa

dashboard/modules/job/tests/test_job_manager.py

@@ -9,8 +9,8 @@ import signal
 import pytest
 
 import ray
+from ray.job_submission import JobStatus
 from ray.dashboard.modules.job.common import (
-    JobStatus,
     JOB_ID_METADATA_KEY,
     JOB_NAME_METADATA_KEY,
 )

dashboard/modules/snapshot/snapshot_head.py

@@ -16,8 +16,8 @@ from ray.experimental.internal_kv import (
 import ray.dashboard.utils as dashboard_utils
 import ray.dashboard.optional_utils as dashboard_optional_utils
 from ray._private.runtime_env.validation import ParsedRuntimeEnv
+from ray.job_submission import JobStatusInfo
 from ray.dashboard.modules.job.common import (
-    JobStatusInfo,
     JobStatusStorageClient,
     JOB_ID_METADATA_KEY,
 )

dashboard/modules/snapshot/tests/test_job_submission.py

@@ -15,7 +15,7 @@ from ray._private.test_utils import (
 )
 from ray.dashboard import dashboard
 from ray.dashboard.tests.conftest import *  # noqa
-from ray.dashboard.modules.job.sdk import JobSubmissionClient
+from ray.job_submission import JobSubmissionClient
 
 logger = logging.getLogger(__name__)
 

doc/source/cluster/job-submission.rst

@@ -143,7 +143,7 @@ We can import and initialize the Job submission client by providing a valid Ray
 
 .. code-block:: python
 
-    from ray.dashboard.modules.job.sdk import JobSubmissionClient
+    from ray.job_submission import JobSubmissionClient
 
     client = JobSubmissionClient("http://127.0.0.1:8265")
 
@@ -169,7 +169,7 @@ Now we can have a simple polling loop that checks the job status until it reache
 
 .. code-block:: python
 
-    from ray.dashboard.modules.job.common import JobStatus, JobStatusInfo
+    from ray.job_submission import JobStatus
 
     def wait_until_finish(job_id):
         start = time.time()

python/ray/job_submission/__init__.py

@@ -0,0 +1,4 @@
+from ray.dashboard.modules.job.sdk import JobSubmissionClient
+from ray.dashboard.modules.job.common import JobStatus, JobStatusInfo
+
+__all__ = ["JobSubmissionClient", "JobStatus", "JobStatusInfo"]