AWS Security Groups not cleaned up in the case of failure

## Expected Behaviour
If there's a failure creating the ec2 instance, then all associated resources (in this case SG) should be cleaned up.

## Current Behaviour
The ec2 instance creation fails and leaves the SG created in place.

## Possible Solution
see expected behavior

## Steps to Reproduce (for bugs)
```
./inletsctl create -f ~/Downloads/access-key --secret-key-file ~/Downloads/secret-access-key -r us-west-2 -z us-west-2c -p ec2
```

## Context

## Your Environment

* inlets version `inlets --version`

* Docker/Kubernetes version `docker version` / `kubectl version`:

* Operating System and version (e.g. Linux, Windows, MacOS):

* Link to your project or a code example to reproduce issue: