Add Flaky to list of test constants

Author: cormacpayne

src/ResourceManager/Common/Commands.ScenarioTests.ResourceManager.Common/Constants.cs

@@ -65,6 +65,8 @@ public class Category
         public const string BVT = "BVT";
 
         public const string CheckIn = "CheckIn";
+        
+        public const string Flaky = "Flaky";
 
         // Run Type
         public const string RunType = "RunType";