do not use ioutil (#9206)

state/indexer/sink/psql/psql_test.go

@@ -5,7 +5,6 @@ import (
 	"database/sql"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/signal"
@@ -227,7 +226,7 @@ func newTestBlockHeader() types.EventDataNewBlockHeader {
 // readSchema loads the indexing database schema file
 func readSchema() ([]*schema.Migration, error) {
 	const filename = "schema.sql"
-	contents, err := ioutil.ReadFile(filename)
+	contents, err := os.ReadFile(filename)
 	if err != nil {
 		return nil, fmt.Errorf("failed to read sql file from '%s': %w", filename, err)
 	}

state/state.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"time"
 
 	"github.com/gogo/protobuf/proto"
@@ -303,7 +303,7 @@ func MakeGenesisStateFromFile(genDocFile string) (State, error) {
 
 // MakeGenesisDocFromFile reads and unmarshals genesis doc from the given file.
 func MakeGenesisDocFromFile(genDocFile string) (*types.GenesisDoc, error) {
-	genDocJSON, err := ioutil.ReadFile(genDocFile)
+	genDocJSON, err := os.ReadFile(genDocFile)
 	if err != nil {
 		return nil, fmt.Errorf("couldn't read GenesisDoc file: %v", err)
 	}

state/txindex/kv/kv_bench_test.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"crypto/rand"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"testing"
 
 	dbm "github.com/tendermint/tm-db"
@@ -15,7 +15,7 @@ import (
 )
 
 func BenchmarkTxSearch(b *testing.B) {
-	dbDir, err := ioutil.TempDir("", "benchmark_tx_search_test")
+	dbDir, err := os.MkdirTemp("", "benchmark_tx_search_test")
 	if err != nil {
 		b.Errorf("failed to create temporary directory: %s", err)
 	}

state/txindex/kv/kv_test.go

@@ -3,7 +3,6 @@ package kv
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"testing"
 
@@ -329,7 +328,7 @@ func txResultWithEvents(events []abci.Event) *abci.TxResult {
 }
 
 func benchmarkTxIndex(txsCount int64, b *testing.B) {
-	dir, err := ioutil.TempDir("", "tx_index_db")
+	dir, err := os.MkdirTemp("", "tx_index_db")
 	require.NoError(b, err)
 	defer os.RemoveAll(dir)