[extractor] Use classmethod/property where possible

and refactor lazy extractors accordingly.

This reduces the need to create extractor instances

yt_dlp/extractor/drtv.py

@@ -18,6 +18,7 @@ from ..utils import (
     url_or_none,
 )
 
+
 class DRTVIE(InfoExtractor):
     _VALID_URL = r'''(?x)
                     https?://