[extractor/BiliIntl] Support uppercase lang in `_VALID_URL`

Seen in some rare cases
Authored by: coletdjnz

yt_dlp/extractor/bilibili.py

@@ -909,7 +909,7 @@ class BiliIntlBaseIE(InfoExtractor):
 
 
 class BiliIntlIE(BiliIntlBaseIE):
-    _VALID_URL = r'https?://(?:www\.)?bili(?:bili\.tv|intl\.com)/(?:[a-z]{2}/)?(play/(?P<season_id>\d+)/(?P<ep_id>\d+)|video/(?P<aid>\d+))'
+    _VALID_URL = r'https?://(?:www\.)?bili(?:bili\.tv|intl\.com)/(?:[a-zA-Z]{2}/)?(play/(?P<season_id>\d+)/(?P<ep_id>\d+)|video/(?P<aid>\d+))'
     _TESTS = [{
         # Bstation page
         'url': 'https://www.bilibili.tv/en/play/34613/341736',
@@ -952,6 +952,10 @@ class BiliIntlIE(BiliIntlBaseIE):
         # No language in URL
         'url': 'https://www.bilibili.tv/video/2019955076',
         'only_matching': True,
+    }, {
+        # Uppercase language in URL
+        'url': 'https://www.bilibili.tv/EN/video/2019955076',
+        'only_matching': True,
     }]
 
     def _real_extract(self, url):
@@ -975,7 +979,7 @@ class BiliIntlIE(BiliIntlBaseIE):
 
 
 class BiliIntlSeriesIE(BiliIntlBaseIE):
-    _VALID_URL = r'https?://(?:www\.)?bili(?:bili\.tv|intl\.com)/(?:[a-z]{2}/)?play/(?P<id>\d+)/?(?:[?#]|$)'
+    _VALID_URL = r'https?://(?:www\.)?bili(?:bili\.tv|intl\.com)/(?:[a-zA-Z]{2}/)?play/(?P<id>\d+)/?(?:[?#]|$)'
     _TESTS = [{
         'url': 'https://www.bilibili.tv/en/play/34613',
         'playlist_mincount': 15,
@@ -993,6 +997,9 @@ class BiliIntlSeriesIE(BiliIntlBaseIE):
     }, {
         'url': 'https://www.biliintl.com/en/play/34613',
         'only_matching': True,
+    }, {
+        'url': 'https://www.biliintl.com/EN/play/34613',
+        'only_matching': True,
     }]
 
     def _entries(self, series_id):