Getting a Cycle error when trying to run apply for Chapter 4

[micronaut]

Hi, I am going through the exercise in Chapter 4. When I try to do terraform apply, I am getting this error.

Error: Cycle: module.networking.module.websvr_sg.var.ingress_rules (expand), module.networking.module.websvr_sg.local.ingress_rules (expand), module.networking.module.websvr_sg.aws_security_group.security_group, module.networking.module.websvr_sg.output.security_group (expand)

I thought maybe it was a typo in my code, but I copied the code from this repo and get the same error.

Thanks!