update documentation

Author: web-flow

docs/lnd/release-notes/release-notes-0.20.0.md

@@ -97,6 +97,7 @@ circuit. The indices are only available for forwarding events saved after v0.20.
     * [11](https://github.com/lightningnetwork/lnd/pull/9972)
   * Add graph SQL migration logic:
     * [1](https://github.com/lightningnetwork/lnd/pull/10036)
+    * [2](https://github.com/lightningnetwork/lnd/pull/10050)
 
 ## RPC Updates
 * Previously the `RoutingPolicy` would return the inbound fee record in its