message: doc: Add release notes for 15596
diff: @@ -66,9 +66,21 @@ platform.
  Notable changes
  ===============
  -Example item
  +Updated RPCs
  ------------
  +Note: some low-level RPC changes mainly useful for testing are described in the
  +Low-level Changes section below.
  +
  +* The `sendmany` RPC had an argument `minconf` that was not well specified and
  + would lead to RPC errors even when the wallet's coin selection would succeed.
  + The `sendtoaddress` RPC never had this check, so to normalize the behavior,
  + `minconf` is now ignored in `sendmany`. If the coin selection does not
  + succeed due to missing coins, it will still throw an RPC error. Be reminded
  + that coin selection is influenced by the `-spendzeroconfchange`,
  + `-limitancestorcount`, `-limitdescendantcount` and `-walletrejectlongchains`
  + command line arguments.
  +
  Low-level changes
  =================
  