incorporated PR comments for policy placeholders

Author: sudhakar4171

src/ResourceManager/RecoveryServices.Backup/Commands.RecoveryServices.Backup.Models/BaseObjects.cs

@@ -55,21 +55,21 @@ public class AzureRmRecoveryServicesPolicyBase : AzureRmRecoveryServicesObjectBa
 
         public WorkloadType WorkloadType { get; set; }
 
-        public virtual void Validate()
+        public override void Validate()
         {
         }
     }
 
     public class AzureRmRecoveryServicesRetentionPolicyBase : AzureRmRecoveryServicesObjectBase
     {
-        public virtual void Validate()
+        public override void Validate()
         {
         }
     }
 
     public class AzureRmRecoveryServicesSchedulePolicyBase : AzureRmRecoveryServicesObjectBase
     {
-        public virtual void Validate()
+        public override void Validate()
         {
         }
     }  

src/ResourceManager/RecoveryServices.Backup/Commands.RecoveryServices.Backup.Models/CommonModels/Enums.cs

@@ -45,7 +45,7 @@ public enum ContainerRegistrationStatus
     }
 
     #region policy
-    public enum WeekNumber
+    public enum WeekOfMonth
     {
         Invalid = 0,
         First = 1,

src/ResourceManager/RecoveryServices.Backup/Commands.RecoveryServices.Backup.Models/CommonModels/PolicyRetentionObjects.cs

@@ -345,7 +345,7 @@ public class WeeklyRetentionFormat
     {
         public List<DayOfWeek> DaysOfTheWeek { get; set; }
 
-        public List<WeekNumber> WeeksOfTheMonth { get; set; }
+        public List<WeekOfMonth> WeeksOfTheMonth { get; set; }
 
         public void Validate()
         {
@@ -360,9 +360,9 @@ public void Validate()
             }
 
             // validate if WeeksOfTheMonth are valid
-            foreach (WeekNumber week in WeeksOfTheMonth)
+            foreach (WeekOfMonth week in WeeksOfTheMonth)
             {
-                if (week == WeekNumber.Invalid)
+                if (week == WeekOfMonth.Invalid)
                 {
                     throw new ArgumentException("WeeksOfTheMonth content is Invalid");
                 }