SNOW-2019505 fix inconsistent force_put_overwrite value for _upload a… (#2247)

Author: sfc-gh-zyao

src/snowflake/connector/cursor.py

@@ -1811,6 +1811,7 @@ def _upload(
             self,
             "",  # empty command because it is triggered by directly calling this util not by a SQL query
             ret,
+            force_put_overwrite=False,  # _upload should respect user decision on overwriting
         )
         file_transfer_agent.execute()
         self._init_result_and_meta(file_transfer_agent.result())
@@ -1878,6 +1879,7 @@ def _upload_stream(
             "",  # empty command because it is triggered by directly calling this util not by a SQL query
             ret,
             source_from_stream=input_stream,
+            force_put_overwrite=False,  # _upload_stream should respect user decision on overwriting
         )
         file_transfer_agent.execute()
         self._init_result_and_meta(file_transfer_agent.result())