fix: Update for location. (#238)

# Pull Request

## Issue
fix: Update the location after using the starter_locations instead of
the default location.

## Description

Description of changes:

## License

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under the terms of the projects associated license.

docs/wiki/[User-Guide]-Starter-Module-Terraform-Sovereign-Landing-Zone.md

@@ -172,7 +172,7 @@ locals {
 
 ### Multiple Inputs for Location
 
-The inputs for `bootstrap_location` and `starter_locations` and `default_location` must be identical. In a future release, we will have defaults and overrides for these values.
+The inputs for `bootstrap_location` and `starter_locations` must be identical, using the first region in starter_locations as the default location. Therefore, starter_locations is required and must include at least one region. In a future release, we will have defaults and overrides for these values.
 
 ### Terraform Plan or Apply Fails After Updating tfvars