Renamed InstanceId to ContainerId due to conflicts with top level objects.

Author: dragonfly91

src/ResourceManager/AzureBackup/Commands.AzureBackup/Models/AzureBackupContainer.cs

@@ -43,7 +43,7 @@ public class AzureBackupContainer : AzureBackupVaultContextObject
         /// <summary>
         /// Id of the Azure Backup Container
         /// </summary>
-        public string InstanceId { get; set; }
+        public string ContainerId { get; set; }
 
         /// <summary>
         /// Name of the Azure Backup container