meta: refactor migration test a bit

Use complete DB reload to get closer to how node works in real life, it
usually opens an existing DB and any open/init code can affect the result.

Signed-off-by: Roman Khimov <[email protected]>

pkg/local_object_storage/metabase/version_test.go

@@ -11,6 +11,7 @@ import (
 	"testing"
 
 	objectconfig "github.com/nspcc-dev/neofs-node/cmd/neofs-node/config/object"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/shard/mode"
 	apistatus "github.com/nspcc-dev/neofs-sdk-go/client/status"
 	"github.com/nspcc-dev/neofs-sdk-go/object"
 	oid "github.com/nspcc-dev/neofs-sdk-go/object/id"
@@ -307,16 +308,20 @@ func TestMigrate2to3(t *testing.T) {
 	})
 	require.NoError(t, err)
 
+	// inhumeV2 stores data in the old format, but new DB has current version by default, force old version.
 	err = db.boltDB.Update(func(tx *bbolt.Tx) error {
-		err = updateVersion(tx, 2)
-		if err != nil {
-			return err
-		}
-
-		return migrateFrom2Version(db, tx)
+		return updateVersion(tx, 2)
 	})
 	require.NoError(t, err)
 
+	db.mode = mode.DegradedReadOnly // Force reload.
+	ok, err := db.Reload(WithPath(db.info.Path), WithEpochState(epochState{}))
+	require.True(t, ok)
+	require.NoError(t, err)
+
+	err = db.Init() // Migration happens here.
+	require.NoError(t, err)
+
 	err = db.boltDB.View(func(tx *bbolt.Tx) error {
 		return tx.Bucket(graveyardBucketName).ForEach(func(k, v []byte) error {
 			require.Len(t, v, addressKeySize+8)