JSONDecodeError when all IDS are duplicated from Ralph

[Ian2012]

When backfilling tracking logs is common to process already stored tracking logs, if a batch is sent to Ralph and all events are already stored the response is empty and cannot be parsed to JSON, raising a JSONDecodeError and stopping the process.

  File "/openedx/venv/lib/python3.11/site-packages/event_routing_backends/utils/xapi_lrs_client.py", line 75, in bulk_send
    response = self.lrs_client.save_statements(statement_data)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/openedx/venv/lib/python3.11/site-packages/tincan/remote_lrs.py", line 234, in save_statements
    id_list = json.loads(lrs_response.data)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/pyenv/versions/3.11.8/lib/python3.11/json/__init__.py", line 346, in loads
    return _default_decoder.decode(s)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/pyenv/versions/3.11.8/lib/python3.11/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/pyenv/versions/3.11.8/lib/python3.11/json/decoder.py", line 355, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)