NadekoBot.Extensions should now be fully annotated with nullable reference types as well as many classes from NadekoBot.Common

src/NadekoBot/Services/Impl/YtdlOperation.cs

@@ -1,3 +1,4 @@
+#nullable disable
 using System.ComponentModel;
 using System.Diagnostics;
 using System.Text;
@@ -70,4 +71,4 @@ public class YtdlOperation
         while((line = await process.StandardOutput.ReadLineAsync()) != null)
             yield return line;
     }
-}
+}