Fixed document-rag workspace problem (#866)

- Fixed document-rag workspace problem
- OpenAI text-completion processor now puts 'not-set' in the token
  if no token is set (new OpenAI library requires it to be set to
  something.
- Update tests

tests/integration/test_document_rag_integration.py

@@ -54,7 +54,7 @@ class TestDocumentRagIntegration:
     @pytest.fixture
     def mock_fetch_chunk(self):
         """Mock fetch_chunk function that retrieves chunk content from librarian"""
-        async def fetch(chunk_id, user):
+        async def fetch(chunk_id):
             return CHUNK_CONTENT.get(chunk_id, f"Content for {chunk_id}")
         return fetch