chore: remove outdated TODO

Author: nymius

src/plan.rs

@@ -363,8 +363,6 @@ impl Plan<DefiniteDescriptorKey> {
                     data
                 });
 
-            // TODO: TapTree. we need to re-traverse the tree to build it, sigh
-
             let leaf_hash = match data.spend_type {
                 Some(SpendType::KeySpend { internal_key }) => {
                     input.tap_internal_key = Some(internal_key);