asp.net core 5,0 项目中Add-Migration 执行报错 (可能不小心删掉了，安装后真的可以用了！！！)

错误提示：

Add-Migration : The term ‘Add-Migration‘ is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.

解决办法：

nuget 安装最新版本：

Microsoft.EntityFrameworkCore.Tools