Failure: Adjust internal equality impl

Author: andreise

src/core-taggeds-failure/Failure/Failure.T/Failure.T.Equality.Common.cs

@@ -8,7 +8,7 @@ private static Type EqualityContract
         =>
         typeof(Failure<TFailureCode>);
 
-    private static IEqualityComparer<TFailureCode> FailureCodeComparer
+    private static EqualityComparer<TFailureCode> FailureCodeComparer
         =>
         EqualityComparer<TFailureCode>.Default;