[pornhub:gif] extract 'viewkey' and 'timestamp' metadata (#4463)

https://github.com/mikf/gallery-dl/issues/4463#issuecomment-2014550302

gallery_dl/extractor/pornhub.py

@@ -143,6 +143,9 @@ class PornhubGifExtractor(PornhubExtractor):
             "url"  : extr('"contentUrl": "', '"'),
             "date" : text.parse_datetime(
                 extr('"uploadDate": "', '"'), "%Y-%m-%d"),
+            "viewkey"  : extr('From this video: '
+                              '<a href="/view_video.php?viewkey=', '"'),
+            "timestamp": extr('lass="directLink tstamp" rel="nofollow">', '<'),
             "user" : text.remove_html(extr("Created by:", "</div>")),
         }