fix: pass youtube_proxy as a `GenericProxyConfig` type object

backend/open_webui/retrieval/loaders/youtube.py

@@ -83,6 +83,7 @@ class YoutubeLoader:
                 TranscriptsDisabled,
                 YouTubeTranscriptApi,
             )
+            from youtube_transcript_api.proxies import (GenericProxyConfig)
         except ImportError:
             raise ImportError(
                 'Could not import "youtube_transcript_api" Python package. '
@@ -90,10 +91,7 @@ class YoutubeLoader:
             )
 
         if self.proxy_url:
-            youtube_proxies = {
-                "http": self.proxy_url,
-                "https": self.proxy_url,
-            }
+            youtube_proxies = GenericProxyConfig(http_url=self.proxy_url, https_url=self.proxy_url)
             log.debug(f"Using proxy URL: {self.proxy_url[:14]}...")
         else:
             youtube_proxies = None