refactoring

application/src/main/java/org/thingsboard/server/service/install/SqlDatabaseUpgradeService.java

@@ -15,8 +15,6 @@
  */
 package org.thingsboard.server.service.install;
 
-import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
 import lombok.extern.slf4j.Slf4j;
@@ -26,10 +24,8 @@ import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.annotation.Lazy;
 import org.springframework.context.annotation.Profile;
 import org.springframework.stereotype.Service;
-import org.thingsboard.common.util.JacksonUtil;
 import org.thingsboard.server.common.data.EntitySubtype;
 import org.thingsboard.server.common.data.Tenant;
-import org.thingsboard.server.common.data.User;
 import org.thingsboard.server.common.data.id.TenantId;
 import org.thingsboard.server.common.data.page.PageData;
 import org.thingsboard.server.common.data.page.PageLink;
@@ -38,7 +34,6 @@ import org.thingsboard.server.common.data.queue.ProcessingStrategyType;
 import org.thingsboard.server.common.data.queue.Queue;
 import org.thingsboard.server.common.data.queue.SubmitStrategy;
 import org.thingsboard.server.common.data.queue.SubmitStrategyType;
-import org.thingsboard.server.common.data.security.UserCredentials;
 import org.thingsboard.server.dao.asset.AssetDao;
 import org.thingsboard.server.dao.asset.AssetProfileService;
 import org.thingsboard.server.dao.dashboard.DashboardService;
@@ -49,7 +44,6 @@ import org.thingsboard.server.dao.queue.QueueService;
 import org.thingsboard.server.dao.sql.tenant.TenantRepository;
 import org.thingsboard.server.dao.tenant.TenantService;
 import org.thingsboard.server.dao.usagerecord.ApiUsageStateService;
-import org.thingsboard.server.dao.user.UserService;
 import org.thingsboard.server.queue.settings.TbRuleEngineQueueConfiguration;
 import org.thingsboard.server.service.install.sql.SqlDbHelper;