add UART notification for user builds

static/releases.html

@@ -419,6 +419,7 @@
                         <li>Settings: use alternate implementation of Wi-Fi auto-turn-off setting matching the Bluetooth auto-turn-off UX</li>
                         <li>overhaul Wi-Fi auto-turn-off implementation including handling the case of Wi-Fi being turned on without connecting to a network</li>
                         <li>add lower auto-reboot timeout options</li>
+                        <li>display notification that UART is enabled in user builds too (where it isn't supported by userspace, but still provides firmware and kernel logs) rather than only in userdebug builds</li>
                     </ul>
                 </article>
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