Tackle AWS068: EKS cluster should not have open CIDR range for public access

[AntoineAugusti]

See documentation https://tfsec.dev/docs/aws/AWS068/

Our current configuration is set this way, is this enough?

notification-terraform/aws/eks/eks.tf

Lines 11 to 16 in a5dfb25

	vpc_config {
	security_group_ids = [
	aws_security_group.notification-canada-ca-worker.id
	]
	subnet_ids = var.vpc_private_subnets
	}

@maxneuvians can you advise and maybe even propose a PR?