feature: warn on 'Stopped' (non-Completed) jobs

Jobs ending with status "Stopped" rather than "Completed" are likely
to have been terminated in non-happy-path: e.g. aborted or stopped
early. Warn users to check results in this case.

Author: athewsey

src/sagemaker/session.py

@@ -2946,7 +2946,13 @@ def _check_job_status(self, job, desc, status_key_name):
         # If the status is capital case, then convert it to Camel case
         status = _STATUS_CODE_TABLE.get(status, status)
 
-        if status not in ("Completed", "Stopped"):
+        if status == "Stopped":
+            LOGGER.warning(
+                "Job ended with status 'Stopped' rather than 'Completed'. "
+                "This could mean the job timed out or stopped early for some other reason: "
+                "Consider checking whether it completed as you expect."
+            )
+        elif status != "Completed":
             reason = desc.get("FailureReason", "(No reason provided)")
             job_type = status_key_name.replace("JobStatus", " job")
             raise exceptions.UnexpectedStatusException(