[cbsnews] Handle iframes with src (closes #24790)

Currently only iframes with a data-src attribute are recognised by the
extractor, meaning no video is found for the URL in the linked bug
(extraction fails with RegexNotFoundError).

This fix removes "data-" from the regex pattern, meaning both data-src
and src will be matched. Technically something like xyzsrc would be
matched as well, but I do not think this is a problem.

youtube_dl/extractor/cbsnews.py

@@ -95,7 +95,8 @@ class CBSNewsIE(CBSIE):
         webpage = self._download_webpage(url, display_id)
 
         entries = []
-        for embed_url in re.findall(r'<iframe[^>]+data-src="(https?://(?:www\.)?cbsnews\.com/embed/video/[^#]*#[^"]+)"', webpage):
+        # This regex is intended to match attributes src and data-src
+        for embed_url in re.findall(r'<iframe[^>]+src="(https?://(?:www\.)?cbsnews\.com/embed/video/[^#]*#[^"]+)"', webpage):
             entries.append(self.url_result(embed_url, CBSNewsEmbedIE.ie_key()))
         if entries:
             return self.playlist_result(