fix: add av1 to webm

At least AV1 in WebM is supported by Chrome and Firefox.

MediaBrowser.MediaEncoding/Probing/ProbeResultNormalizer.cs

@@ -30,7 +30,7 @@ namespace MediaBrowser.MediaEncoding.Probing
         private const string ArtistReplaceValue = " | ";
 
         private readonly char[] _nameDelimiters = { '/', '|', ';', '\\' };
-        private readonly string[] _webmVideoCodecs = { "vp8", "vp9" };
+        private readonly string[] _webmVideoCodecs = { "av1", "vp8", "vp9" };
         private readonly string[] _webmAudioCodecs = { "opus", "vorbis" };
 
         private readonly ILogger _logger;