Updating numbering and removing duplicate requirements

Author: LuizMacedo

Instructions/Labs/AZ400_M04_L09_Controlling_Deployments_using_Release_Gates.md

@@ -52,25 +52,6 @@ After you complete this lab, you will be able to:
 
 ## Instructions
 
-### Before you start
-
-#### Sign in to the lab virtual machine
-
-Ensure that you're signed in to your Windows 10 computer by using the following credentials:
-    
--   Username: **Student**
--   Password: **Pa55w.rd**
-
-#### Review applications required for this lab
-
-Identify the applications that you'll use in this lab:
-    
--   Microsoft Edge
-
-#### Set up an Azure DevOps organization. 
-
-If you don't already have an Azure DevOps organization that you can use for this lab, create one by following the instructions available at [Create an organization or project collection](https://docs.microsoft.com/en-us/azure/devops/organizations/accounts/create-organization?view=azure-devops).
-
 ### Exercise 0: Configure the lab prerequisites
 
 In this exercise, you will set up the prerequisites for the lab, which consist of a new Azure DevOps project with a repository based on the [eShopOnWeb](https://dev.azure.com/unhueteb/_git/eshopweb-az400).
@@ -300,7 +281,7 @@ In this task, you will enable the post-deployment gate for the Canary Environmen
 1. Close the **Post-deployment conditions** pane, by clicking the **x** mark in its upper right corner.
 1. Back on the **New Release Pipeline** pane, click **Save**, and in the **Save** dialog box, click **OK**.
 
-### Exercise 3: Test release gates
+### Exercise 4: Test release gates
 
 In this exercise, you will test the release gates by updating the application, which will trigger a deployment.
 
@@ -325,7 +306,7 @@ In this task, you will track the release process with the release gates enabled.
 
 1. Wait another 3 minutes and validate the status of the Release Gates again. As it is now +8 minutes after the initial Release Gates got checked, and it's been more than 8 minutes since the initial Application Insight Alert got triggered with action "Fired", it should result in a successful Release Gate, having allowed the deployment of the Production Release Stage as well.
 
-### Exercise 4: Remove the Azure lab resources
+### Exercise 5: Remove the Azure lab resources
 
 In this exercise, you will remove the Azure resources provisioned in this lab to eliminate unexpected charges.