fix typo

Author: Brian969

docs/installation/installation.md

@@ -383,7 +383,7 @@ Finally, while we started with a goal of delivering on the 12 guardrails, we bel
 ## 3.1. Upgrades
 
 - Always compare your configuration file with the config file from the latest release to validate new or changed parameters or changes in parameter types / formats.
-- Upgrades to `v1.2.2 and above` from v1.2.1 and below - if more than 5 VPC endpoints are deployed in any account (i.e. endpoint vpc in the shared network account), before upgrade, they must be removed from the config file and state machine executed to de-provision them. Endpoints can be re-deployed during the upgrade state machine execution. Skipping this step will result in an upgrade failure due to throttling issues.
+- Upgrades to `v1.2.1 and above` from v1.2.0 and below - if more than 5 VPC endpoints are deployed in any account (i.e. endpoint vpc in the shared network account), before upgrade, they must be removed from the config file and state machine executed to de-provision them. Endpoints can be re-deployed during the upgrade state machine execution. Skipping this step will result in an upgrade failure due to throttling issues.
 - Upgrades to `v1.2.0 and above` from v1.1.9 and below require setting `account-warming-required` to `false`, (Perimeter and Ops accounts) or the rsyslog and firewalls will be removed and then re-installed on the subsequent state machine execution
 - Upgrades from `v1.1.7 and below` require the one-time removal of incorrectly created and associated resolver rules for private DNS domains. While we created a manual [script](../reference-artifacts/Custom-Scripts/resolver-rule-cleanup.sh) to remove the incorrect associations, it is quicker to manually delete the incorrect associations using the console (`shared-network` account, Route 53, Resolvers).
 - Upgrades from `v1.1.6 and below` require updating the `GithubRepository` in the CFN stack, as we renamed the GitHub repo with release v1.1.7 to `aws-secure-environment-accelerator`.