IPv6 Addresses can't be added to cidr_block

[Stretch96]

The default for public_alb_whitelist is set to ["0.0.0.0/0", "::/0"]

This makes the module, with default settings error:

* aws_security_group.alb_sg: Error authorizing security group ingress rules: InvalidParameterValue: CIDR block ::/0 is malformed

hashicorp/terraform#14382

We need to use ipv6_cidr_blocks if we want to implement IPv6:

resource "aws_security_group" "test" {
  vpc_id = "${var.vpc}"
  name        = "Test"
  description = "Test"

  # Allow all outgoing:
  egress {
    from_port       = 0
    to_port         = 0
    protocol        = "-1"
    cidr_blocks     = ["0.0.0.0/0"]
  }
  egress {
    from_port       = 0
    to_port         = 0
    protocol        = "-1"
    ipv6_cidr_blocks     = ["::/0"]
  }
}

A workaround is just to set public_alb_whitelist to ["0.0.0.0/0"] (Or your list of IPv4 addresses)

I'll open a PR to just remove the "::/0" from the default for now

[easyrun32]

ipv6_cidr_blocks = ["::/0"]