[cleanup] Update extractor tests (#7718)

Authored by: trainman261

yt_dlp/extractor/nationalgeographic.py

@@ -24,6 +24,7 @@ class NationalGeographicVideoIE(InfoExtractor):
                 'uploader': 'NAGS',
             },
             'add_ie': ['ThePlatform'],
+            'skip': 'Redirects to main page',
         },
         {
             'url': 'http://video.nationalgeographic.com/wild/when-sharks-attack/the-real-jaws',
@@ -38,6 +39,7 @@ class NationalGeographicVideoIE(InfoExtractor):
                 'uploader': 'NAGS',
             },
             'add_ie': ['ThePlatform'],
+            'skip': 'Redirects to main page',
         },
     ]
 
@@ -75,6 +77,7 @@ class NationalGeographicTVIE(FOXIE):  # XXX: Do not subclass from concrete IE
         'params': {
             'skip_download': True,
         },
+        'skip': 'Content not available',
     }]
     _HOME_PAGE_URL = 'https://www.nationalgeographic.com/tv/'
     _API_KEY = '238bb0a0c2aba67922c48709ce0c06fd'