refactor: keep batch.Close error handle logic consistance (#21812)

store/rootmulti/store.go

@@ -1147,7 +1147,9 @@ func (rs *Store) flushMetadata(db corestore.KVStoreWithBatch, version int64, cIn
 	rs.logger.Debug("flushing metadata", "height", version)
 	batch := db.NewBatch()
 	defer func() {
-		_ = batch.Close()
+		if err := batch.Close(); err != nil {
+			rs.logger.Error("call flushMetadata error on batch close", "err", err)
+		}
 	}()
 
 	if cInfo != nil {

store/v2/commitment/metadata.go

@@ -2,6 +2,7 @@ package commitment
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 
 	corestore "cosmossdk.io/core/store"
@@ -158,9 +159,7 @@ func (m *MetadataStore) deleteRemovedStoreKeys(version uint64, removeStore func(
 
 	batch := m.kv.NewBatch()
 	defer func() {
-		if berr := batch.Close(); berr != nil {
-			err = berr
-		}
+		err = errors.Join(err, batch.Close())
 	}()
 	for _, storeKey := range removedStoreKeys {
 		if err := removeStore(storeKey, version); err != nil {