chore/perf: Remove old SRC level log env vars with no impact (#20045)

* Update openai.py

* Update env.py

* Merge pull request open-webui#19030 from open-webui/dev (#119)

Co-authored-by: Tim Baek <tim@openwebui.com>
Co-authored-by: Claude <noreply@anthropic.com>

---------

Co-authored-by: Tim Baek <tim@openwebui.com>
Co-authored-by: Claude <noreply@anthropic.com>

backend/open_webui/routers/retrieval.py

@@ -99,7 +99,6 @@ from open_webui.config import (
     RAG_EMBEDDING_QUERY_PREFIX,
 )
 from open_webui.env import (
-    SRC_LOG_LEVELS,
     DEVICE_TYPE,
     DOCKER,
     SENTENCE_TRANSFORMERS_BACKEND,
@@ -111,7 +110,6 @@ from open_webui.env import (
 from open_webui.constants import ERROR_MESSAGES
 
 log = logging.getLogger(__name__)
-log.setLevel(SRC_LOG_LEVELS["RAG"])
 
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