SIENTIAPDE-1318

Refactor app.py and enhance unit tests for better clarity and structure

- Updated `app.py` to improve async compatibility with a clearer comment.
- Added blank lines in `test_ingestor.py` for improved readability and organization of test cases.

ingestor/app.py

@@ -55,7 +55,7 @@ async def main():
             metrics.APP_LOOP_COUNT.labels(pod_id=POD_ID).inc()  # Increment loop counter
 
             # Use asyncio.sleep instead of exit_signal.wait for better async compatibility
-            await asyncio.sleep(ingestor.poll_interval) # NOSONAR
+            await asyncio.sleep(ingestor.poll_interval)  # NOSONAR
 
         except KeyboardInterrupt:  # Handle Ctrl+C gracefully
             print('KeyboardInterrupt received. Setting exit_signal flag.')