Remove sdk version

Author: HaoK

eng/helix/content/RunTests/RunTestsOptions.cs

@@ -21,11 +21,6 @@ public static RunTestsOptions Parse(string[] args)
                     description: "The test dll to run")
                     { Argument = new Argument<string>(), Required = true },
 
-                new Option(
-                    aliases: new string[] { "--sdk" },
-                    description: "The version of the sdk being used")
-                { Argument = new Argument<string>(), Required = true },
-
                 new Option(
                     aliases: new string[] { "--runtime" },
                     description: "The version of the runtime being used")
@@ -70,7 +65,6 @@ public static RunTestsOptions Parse(string[] args)
             var parseResult = command.Parse(args);
             var options = new RunTestsOptions();
             options.Target = parseResult.ValueForOption<string>("--target");
-            options.SdkVersion = parseResult.ValueForOption<string>("--sdk");
             options.RuntimeVersion = parseResult.ValueForOption<string>("--runtime");
             options.HelixQueue = parseResult.ValueForOption<string>("--queue");
             options.Architecture = parseResult.ValueForOption<string>("--arch");
@@ -86,7 +80,6 @@ public static RunTestsOptions Parse(string[] args)
         }
 
         public string Target { get; set;}
-        public string SdkVersion { get; set;}
         public string RuntimeVersion { get; set;}
         public string AspNetRuntime { get; set;}
         public string AspNetRef { get; set;}