Update clean_podcast_url() in _utils.py

Fix for yt-dlp#7430 and yt-dlp#7544
Example URLs:
https://pdst.fm/e/2.gum.fm/chtbl.com/track/chrt.fm/track/34D33/pscrb.fm/rss/p/traffic.megaphone.fm/ITLLC7765286967.mp3?updated=1687282661

https://pdst.fm/e/https://mgln.ai/e/441/www.buzzsprout.com/1121972/13019085-ep-252-the-deep-life-stack.mp3

yt_dlp/utils/_utils.py

@@ -5118,9 +5118,9 @@ def format_field(obj, field=None, template='%s', ignore=NO_DEFAULT, default='',
 
 
 def clean_podcast_url(url):
-    url = re.sub(r'''(?x)
+    return re.sub(r'''(?x)
         (?:
-            (?:
+            (\w+://)(?:
                 chtbl\.com/track|
                 media\.blubrry\.com| # https://create.blubrry.com/resources/podcast-media-download-statistics/getting-started/
                 play\.podtrac\.com
@@ -5132,7 +5132,6 @@ def clean_podcast_url(url):
                 st\.fm # https://podsights.com/docs/
             )/e
         )/''', '', url)
-    return re.sub(r'^\w+://(\w+://)', r'\1', url)
 
 
 _HEX_TABLE = '0123456789abcdef'