Fix thumbnail directory creation logic

Author: tushar1977

backend/main.py

@@ -43,8 +43,7 @@
 path = os.path.dirname(DATABASE_PATH)
 os.makedirs(path, exist_ok=True)
 
-thumbnail_path = os.path.dirname(THUMBNAIL_IMAGES_PATH)
-os.makedirs(thumbnail_path, exist_ok=True)
+os.makedirs(THUMBNAIL_IMAGES_PATH, exist_ok=True)
 
 
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