Move ToHashSet to ServiceStack.Extensions

Author: mythz

src/ServiceStack.Text/Extensions/ServiceStackExtensions.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 
 namespace ServiceStack.Extensions
 {
@@ -8,7 +9,6 @@ namespace ServiceStack.Extensions
     public static class ServiceStackExtensions
     {
         //Ambiguous definitions in .NET Core 3.0 System MemoryExtensions.cs 
-        
         public static ReadOnlyMemory<char> Trim(this ReadOnlyMemory<char> span)
         {
             return span.TrimStart().TrimEnd();
@@ -39,6 +39,8 @@ public static ReadOnlyMemory<char> TrimEnd(this ReadOnlyMemory<char> value)
             }
             return value.Slice(0, end + 1);
         }
-        
+
+        // Ambiguous with System.Linq v4.7.2
+        public static HashSet<T> ToHashSet<T>(this IEnumerable<T> items) => new HashSet<T>(items);
     }
 }