The default value `ebs_optimized = true` makes some instance types unable to provision.

### Describe the Bug

Because the default value of `ebs_optimized` changed to true in this PR #159, some instance types (such as t2.micro) are unable to provision because they are simply unsupported for EBS-optimized instances.
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-optimized.html

So the following code causes an error:

```
module "my-ec2" {
source = "cloudposse/ec2-instance/aws"
version = "1.1.0"

vpc_id = module.shared_vpc.vpc_id

ami = "ami-06fdbb60c8e83aa5e"
instance_type = "t2.micro"
ami_owner = "137112412989"
subnet = module.shared_dynamic_subnets.private_subnet_ids[0]
}
```

```
Error: creating EC2 Instance: Unsupported: The requested configuration is currently not supported. Please check the documentation for supported configurations.
```

### Expected Behavior

EC2 instances of types that do not support EBS-optimized configurations can still be provisioned using default values.

### Steps to Reproduce

Terraform v1.5.6

aws = {
source = "hashicorp/aws"
version = ">=5.12.0, <6.0.0"
}

Then applying the code above will reproduce.

### Screenshots

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### Environment

_No response_

### Additional Context

_No response_