chore: update lab instructions and region selection

- Remove --location flag from azd env new command (location prompted separately)
- Add note about location selection prompt
- Reorder allowed regions in main.bicep (westus first for better availability)

Author: dbarkol

docs/lab-instructions.md

@@ -162,7 +162,7 @@ Now, you'll use the Azure Developer CLI (azd) to *start* provisioning all the ne
 
   An azd environment stores configuration details like subscription ID and location. Create a new environment for this lab (this will be unique to each lab environment):
 
-    `azd env new snippymcplab-@lab.labinstance.id --subscription @lab.cloudsubscription.id --location @lab.cloudresourcegroup(ResourceGroup1).Location`
+    `azd env new snippymcplab-@lab.labinstance.id --subscription @lab.cloudsubscription.id`
 
 4. [] **Set the name suffix for Azure resources:**
 
@@ -182,6 +182,8 @@ Now, you'll use the Azure Developer CLI (azd) to *start* provisioning all the ne
 
     to provision all the Azure resources needed to run snippy. 
 
+    If prompted, select a location from the terminal to deploy the Azure resources.
+
     > [!knowledge] This command provisions Azure resources such as:
     >   * Azure Function App (using the scalable Flex Consumption plan)
     >   * Azure Storage Account (for Functions operations and state)

infra/main.bicep

@@ -7,7 +7,7 @@ param environmentName string
 
 @minLength(1)
 @description('Primary location for all resources')
-@allowed([ 'eastus2', 'westus', 'westus2', 'westus3'])
+@allowed([ 'westus', 'westus2', 'westus3', 'eastus2'])
 @metadata({
   azd: {
     type: 'location'