ec2_platform: Named security groups are not unique to job runs

[syndr]

If a security group is specified by name, all job runs will match the same group based on specifically that name. This becomes an issue when there are multiple test jobs running concurrently, as the destroy step of one job will remove the security group that is being used by the other (still running) job.

Named security groups are necessary for any tests where multiple instances need to communicate with each other (any clustered application).

These groups should have a tag applied with the unique ID for the currently running Molecule job, and adds/deletes should filter based upon that value to avoid trampling on other tests.

[syndr]

This should probably be updated to skip the delete step if the security group doesn't have a tag on it for the currently running job. Furthermore, if the security group already exists, that tag should not be added in order to prevent destruction of SGs that have relevance outside of a particular molecule job run.