Add note for Auto-upgrade unsupported for AMI instances (#578)

Add note for Auto-upgrade state being unsupported for AMI instances

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Author: morgangauth

docs/admin/deploy/machine-images/aws-ami.mdx

@@ -170,7 +170,7 @@ Now that your instance is confirmed to be working, and you have HTTPS working th
 
 <Callout type="warning">This upgrade process works with **Sourcegraph AWS AMI instances only**. Do not use these if you deployed Sourcegraph through other means.</Callout>
 
-<Callout type="warning">Please be aware that our AMI deployment types do not support multi-version upgrades at this time.</Callout>
+<Callout type="warning">Please be aware that our AMI deployment types do not support multi-version upgrades at this time, nor do they support Automatic Upgrade State. The Automatic Upgrade State toggle can be found on your Sourcegraph instance's `site-admin/updates` screen.</Callout>
 
 Please take time to review the following before proceeding with the upgrades: