Update important-changes.mdx to cover aws-auto-join fixed versions for 1.19.x docs (#911)

Update important-changes.mdx to cover aws-auto-join fixed versions in the 1.19.x docs

Co-authored-by: Sarah Chavis <62406755+schavis@users.noreply.github.com>

Author: ram-parameswaran

content/vault/v1.19.x/content/docs/updates/important-changes.mdx

@@ -337,7 +337,7 @@ Explicitly set the default endpoint and region when configuring sts:
 
 | Change      | Status | Affected version               | Fixed version
 | ----------- | ------ | ------------------------------ | --------------------
-| Known issue | Open   | 1.19.5 to 1.19.8, 1.20.x       | None
+| Known issue | Open   | 1.19.5 to 1.19.8, 1.20.x       | 1.19.9,1.20.3
 
 After unsealing Vault and attempting to autojoin nodes to the cluster, if Dual Stack endpoints are not enabled in that region.