test: use T.TempDir to create temporary test directory

The directory created by `T.TempDir` is automatically removed when the
test and all its subtests complete.

Reference: https://pkg.go.dev/testing#T.TempDir
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>

snapshots/storage/metastore_test.go

@@ -20,7 +20,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"os"
 	"testing"
 	"time"
 
@@ -66,17 +65,16 @@ func MetaStoreSuite(t *testing.T, name string, meta func(root string) (*MetaStor
 func makeTest(t *testing.T, name string, metaFn metaFactory, fn testFunc) func(t *testing.T) {
 	return func(t *testing.T) {
 		ctx := context.Background()
-		tmpDir, err := os.MkdirTemp("", "metastore-test-"+name+"-")
-		if err != nil {
-			t.Fatal(err)
-		}
-		defer os.RemoveAll(tmpDir)
 
-		ms, err := metaFn(tmpDir)
+		ms, err := metaFn(t.TempDir())
 		if err != nil {
 			t.Fatal(err)
 		}
 
+		t.Cleanup(func() {
+			ms.Close()
+		})
+
 		fn(ctx, t, ms)
 	}
 }