[#1450] engine/test: Refactor (*testEngineWrapper).setInitializedShards

This function was a duplicate of the `(*StorageEngine).addShard`
but it didn't allow to set an engine's shard pool size what can
be very useful sometimes.

Signed-off-by: Aleksey Savchuk <a.savchuk@yadro.com>

pkg/local_object_storage/engine/engine_test.go

@@ -3,7 +3,6 @@ package engine
 import (
 	"context"
 	"path/filepath"
-	"sync/atomic"
 	"testing"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/blobstor"
@@ -19,8 +18,6 @@ import (
 	objectSDK "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
 	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
 	oidtest "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id/test"
-	"git.frostfs.info/TrueCloudLab/hrw"
-	"github.com/panjf2000/ants/v2"
 	"github.com/stretchr/testify/require"
 )
 
@@ -90,17 +87,7 @@ func testNewEngine(t testing.TB, opts ...Option) *testEngineWrapper {
 
 func (te *testEngineWrapper) setInitializedShards(t testing.TB, shards ...*shard.Shard) *testEngineWrapper {
 	for _, s := range shards {
-		pool, err := ants.NewPool(10, ants.WithNonblocking(true))
-		require.NoError(t, err)
-
-		te.engine.shards[s.ID().String()] = hashedShard{
-			shardWrapper: shardWrapper{
-				errorCount: new(atomic.Uint32),
-				Shard:      s,
-			},
-			hash: hrw.StringHash(s.ID().String()),
-		}
-		te.engine.shardPools[s.ID().String()] = pool
+		require.NoError(t, te.engine.addShard(s))
 		te.shardIDs = append(te.shardIDs, s.ID())
 	}
 	return te