rpc: change default sorting to desc for `/tx_search` results (#6168)

Closes #6155

CHANGELOG_PENDING.md

@@ -14,6 +14,7 @@ Friendly reminder, we have a [bug bounty program](https://hackerone.com/tendermi
   - [cli] \#5772 `gen_node_key` prints JSON-encoded `NodeKey` rather than ID and does not save it to `node_key.json` (@melekes)
   - [cli] \#5777 use hyphen-case instead of snake_case for all cli commands and config parameters (@cmwaters)
   - [rpc] \#6019 standardise RPC errors and return the correct status code (@bipulprasad & @cmwaters)
+  - [rpc] \#6168 Change default sorting to desc for `/tx_search` results (@melekes)
 
 - Apps
   - [ABCI] \#5447 Remove `SetOption` method from `ABCI.Client` interface
@@ -29,7 +30,7 @@ Friendly reminder, we have a [bug bounty program](https://hackerone.com/tendermi
   - [proto/p2p] Renamed `DefaultNodeInfo` and `DefaultNodeInfoOther` to `NodeInfo` and `NodeInfoOther` (@erikgrinaker)
   - [proto/p2p] Rename `NodeInfo.default_node_id` to `node_id` (@erikgrinaker)
   - [libs/os] Kill() and {Must,}{Read,Write}File() functions have been removed. (@alessio)
-  - [store] \#5848 Remove block store state in favor of using the db iterators directly (@cmwaters)  
+  - [store] \#5848 Remove block store state in favor of using the db iterators directly (@cmwaters)
   - [state] \#5864 Use an iterator when pruning state (@cmwaters)
   - [types] \#6023 Remove `tm2pb.Header`, `tm2pb.BlockID`, `tm2pb.PartSetHeader` and `tm2pb.NewValidatorUpdate`.
     - Each of the above types has a `ToProto` and `FromProto` method or function which replaced this logic.

rpc/core/tx.go

@@ -73,14 +73,14 @@ func TxSearch(ctx *rpctypes.Context, query string, prove bool, pagePtr, perPageP
 
 	// sort results (must be done before pagination)
 	switch orderBy {
-	case "desc":
+	case "desc", "":
 		sort.Slice(results, func(i, j int) bool {
 			if results[i].Height == results[j].Height {
 				return results[i].Index > results[j].Index
 			}
 			return results[i].Height > results[j].Height
 		})
-	case "asc", "":
+	case "asc":
 		sort.Slice(results, func(i, j int) bool {
 			if results[i].Height == results[j].Height {
 				return results[i].Index < results[j].Index

rpc/openapi/openapi.yaml

@@ -1004,7 +1004,7 @@ paths:
           required: false
           schema:
             type: string
-            default: "asc"
+            default: "desc"
             example: "asc"
       tags:
         - Info