fix: root management group permissions issue (#200)

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## Overview/Summary

Fix an issue where permissions have not yet propogated from the
accelerator bootstrap

## This PR fixes/adds/changes/removes

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### Breaking Changes

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templates/platform_landing_zone/modules/management_groups/locals.tf

@@ -15,7 +15,7 @@ locals {
   } }
   default_retries = {
     management_groups = {
-      error_message_regex = ["AuthorizationFailed"]
+      error_message_regex = ["AuthorizationFailed", "Permission to Microsoft.Management/managementGroups on resources of type 'Write' is required on the management group or its ancestors."]
     }
     role_definitions = {
       error_message_regex = ["AuthorizationFailed"]