SMO.Server.KillDatabase() throws when targeting a SQL Azure Managed Instance server

Repro:

            var sc3 = new SqlConnection(@"Data Source=<your MI server>;User ID=sa; Password=...");
            var srvconn3 = new ServerConnection(sc3);
            var server3 = new SMO.Server(srvconn3);
            var db3 = new SMO.Database(server3, "MatteoT_1");
            db3.Create();
            server3.KillDatabase(db3.Name);

Result
Runtime exception: This ALTER DATABASE statement is not supported. Correct the syntax and execute the statement again.

It looks like we are tripping over the attempt to put the DB in single user mode:

ALTER DATABASE [MatteoT_1] SET SINGLE_USER WITH ROLLBACK IMMEDIATE

从 SMO.Server.KillDatabase() 开始，使用提供的示例在 SQL Azure Managed Instance 上重现该故障。跟踪生成的 ALTER DATABASE 语句，尤其是 SINGLE_USER 子句；当针对 MI 目标执行 KillDatabase 时不再出现不支持的语法异常，即表示完成。