Update Multi-Tenancy.md

docs/en/Multi-Tenancy.md

@@ -329,6 +329,7 @@ Configure<AbpTenantResolveOptions>(options =>
 `MyCustomTenantResolveContributor` must inherit from the `TenantResolveContributorBase` (or implement the `ITenantResolveContributor`) as shown below:
 
 ````csharp
+using System.Threading.Tasks;
 using Volo.Abp.MultiTenancy;
 
 namespace MultiTenancyDemo.Web
@@ -337,7 +338,7 @@ namespace MultiTenancyDemo.Web
     {
         public override string Name => "Custom";
 
-        public override void Resolve(ITenantResolveContext context)
+        public override Task ResolveAsync(ITenantResolveContext context)
         {
             //TODO...
         }

docs/zh-Hans/Multi-Tenancy.md

@@ -127,13 +127,14 @@ namespace MyCompany.MyProject
 `MyCustomTenantResolveContributor`必须像下面这样实现**ITenantResolveContributor**接口:
 
 ````C#
+using System.Threading.Tasks;
 using Volo.Abp.MultiTenancy;
 
 namespace MyCompany.MyProject
 {
     public class MyCustomTenantResolveContributor : ITenantResolveContributor
     {
-        public void Resolve(ITenantResolveContext context)
+        public override Task ResolveAsync(ITenantResolveContext context)
         {
             context.TenantIdOrName = ... //从其他地方获取租户id或租户名字...
         }