[extractors] Use new framework for existing embeds (#4307)

`Brightcove` is difficult to migrate because it's subclasses may depend
on the signature of the current functions. So it is left as-is for now

Note: Tests have not been migrated

yt_dlp/extractor/sbs.py

@@ -15,6 +15,12 @@ class SBSIE(InfoExtractor):
                 .*?\bplay=|/watch/
             )|news/(?:embeds/)?video/
         )(?P<id>[0-9]+)'''
+    _EMBED_REGEX = [r'''(?x)]
+            (?:
+                <meta\s+property="og:video"\s+content=|
+                <iframe[^>]+?src=
+            )
+            (["\'])(?P<url>https?://(?:www\.)?sbs\.com\.au/ondemand/video/.+?)\1''']
 
     _TESTS = [{
         # Original URL is handled by the generic IE which finds the iframe: