Fix bug forcing uploaded tar to be named sourcedir

Author: claytonparnell

src/sagemaker/processing.py

@@ -1679,10 +1679,8 @@ def _pack_and_upload_code(
             )
 
         # Upload the bootstrapping code as s3://.../jobname/source/runproc.sh.
-        entrypoint_s3_uri = estimator.uploaded_code.s3_prefix.replace(
-            "sourcedir.tar.gz",
-            "runproc.sh",
-        )
+        entrypoint_s3_uri = estimator.uploaded_code.s3_prefix.rsplit('/', 1)[0] + '/runproc.sh'
+
         script = estimator.uploaded_code.script_name
         s3_runproc_sh = S3Uploader.upload_string_as_file_body(
             self._generate_framework_script(script),