Determine check for minimum bash-commons version

[zackproser]

See also https://github.com/gruntwork-io/terraform-aws-server/pull/130#discussion_r727239404

Now that we've migrated many of our repos over to use bash-commons as a dependency, we should think of a reasonable way to check / enforce the minimum version of bash-commons that a module may need.

For example, ensuring that you're at least running v0.1.8 of bash-commons which introduced support for IMDSv2.