Use consistent log file names, introduced initLogger (#3403)

### What problem does this PR solve?

Use consistent log file names, introduced initLogger

### Type of change

- [ ] Bug Fix (non-breaking change which fixes an issue)
- [ ] New Feature (non-breaking change which adds functionality)
- [ ] Documentation Update
- [x] Refactoring
- [ ] Performance Improvement
- [ ] Other (please describe):

rag/app/email.py

@@ -11,6 +11,7 @@
 #  limitations under the License.
 #
 
+import logging
 from email import policy
 from email.parser import BytesParser
 from rag.app.naive import chunk as naive_chunk
@@ -18,7 +19,6 @@ import re
 from rag.nlp import rag_tokenizer, naive_merge, tokenize_chunks
 from deepdoc.parser import HtmlParser, TxtParser
 from timeit import default_timer as timer
-from api.utils.log_utils import logger
 import io
 
 
@@ -86,7 +86,7 @@ def chunk(
     )
 
     main_res.extend(tokenize_chunks(chunks, doc, eng, None))
-    logger.info("naive_merge({}): {}".format(filename, timer() - st))
+    logging.debug("naive_merge({}): {}".format(filename, timer() - st))
     # get the attachment info
     for part in msg.iter_attachments():
         content_disposition = part.get("Content-Disposition")