Embedded Subtitles provider: add support for alpha2 tags

Done by updating the fese library

libs/fese/__init__.py

@@ -4,4 +4,4 @@
 from .container import FFprobeVideoContainer
 from .stream import FFprobeSubtitleStream
 
-__version__ = "0.2.2"
+__version__ = "0.2.3"

libs/fese/tags.py

@@ -128,7 +128,11 @@ def _get_language(tags) -> Language:
                 return Language(*extra["language_args"])
 
         try:
-            lang = Language.fromalpha3b(og_lang)
+            if len(og_lang) == 3:
+                lang = Language.fromalpha3b(og_lang)
+            else:
+                lang = Language.fromalpha2(og_lang[:2])
+
             # Test for suffix
             assert lang.alpha2