Update config.py

Fixed S3_USE_ACCELERATE_ENDPOINT variable from "False" to "false" since boto3 expects a Python bool, not a string.
Added S3_ENABLE_TAGGING env variable to avoid incompatiblilty with Storages that does not support tagging (like Cloudflare R2)

backend/open_webui/config.py

@@ -761,9 +761,10 @@ S3_BUCKET_NAME = os.environ.get("S3_BUCKET_NAME", None)
 S3_KEY_PREFIX = os.environ.get("S3_KEY_PREFIX", None)
 S3_ENDPOINT_URL = os.environ.get("S3_ENDPOINT_URL", None)
 S3_USE_ACCELERATE_ENDPOINT = (
-    os.environ.get("S3_USE_ACCELERATE_ENDPOINT", "False").lower() == "true"
+    os.environ.get("S3_USE_ACCELERATE_ENDPOINT", "false").lower() == "true"
 )
 S3_ADDRESSING_STYLE = os.environ.get("S3_ADDRESSING_STYLE", None)
+S3_ENABLE_TAGGING = os.getenv("S3_ENABLE_TAGGING", "false").lower() == "true"
 
 GCS_BUCKET_NAME = os.environ.get("GCS_BUCKET_NAME", None)
 GOOGLE_APPLICATION_CREDENTIALS_JSON = os.environ.get(