rpc: check error code for broadcast_tx_commit (#7683) (#7688)

(cherry picked from commit 6a02714814)

Co-authored-by: Sam Kleinman <garen@tychoish.com>

internal/rpc/core/mempool.go

@@ -72,6 +72,12 @@ func (env *Environment) BroadcastTxCommit(ctx *rpctypes.Context, tx types.Tx) (*
 	}
 
 	r := (<-resCh).GetCheckTx()
+	if r.Code != abci.CodeTypeOK {
+		return &coretypes.ResultBroadcastTxCommit{
+			CheckTx: *r,
+			Hash:    tx.Hash(),
+		}, fmt.Errorf("transaction encountered error (%s)", r.MempoolError)
+	}
 
 	if !indexer.KVSinkEnabled(env.EventSinks) {
 		return &coretypes.ResultBroadcastTxCommit{