desired_capacity should be optional

[ByJacob]

Found a bug? Maybe our Slack Community can help.

Describe the Bug

When the automatic scaling increases the number of instances and we execute the code from desired_capacity, the number of instances will be set according to the value of desired_capacity, ignoring the current alarm state. If we do not specify desired_capacity, it will be set to the minimum value anyway.

Expected Behavior

When the current number of instances is 2 and we execute the code without desired_capacity , 2 instances will still work.

Steps to Reproduce

Steps to reproduce the behavior:

1. Setup ASG with alarm
2. Trigger allarb (now asg should have 2 insatnce)
3. Apply changes (example change ami)
4. See error

Screenshots

If applicable, add screenshots or logs to help explain your problem.

Environment (please complete the following information):

Anything that will help us triage the bug will help. Here are some ideas:

• OS: linux
• Version 0.22.0

Additional Context

https://github.com/cloudposse/terraform-aws-ec2-autoscale-group/blob/master/main.tf#L141

https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/autoscaling_group#desired_capacity

https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/autoscaling_group#waiting-for-capacity

[Nuru]

Closed by #67