The place where the command timeout is set is no longer the same as earlier versions.
However, I cannot find anywhere that says how to change this.
What I am doi
If you're using the DI container to manage the DbContext (i.e. you're adding the DbContext to the service collection), the command timeout can be specified in the options.
In Startup.ConfigureServices:
services.AddDbContext(options => options.UseSqlServer(
this.Configuration.GetConnectionString("YourConnectionString"),
sqlServerOptions => sqlServerOptions.CommandTimeout(60))
);