With the recent updates to bundler the need for a specific set of gems for each version of ruby that we support has been removed.
As such the logic behind our gems is now much simpler and can easily fit within the default templates, thus removing our need to have a separate module to manage them, with the templates already managing all other similar default requirements for our modules.

Prior to this change only a single version requirement could be passed through to the code.
With this however we can now spec specify multiple, allowing us a much more exact control of our Gems

- Added Rubocop gems missing from original commit
- Add lower bounds to all gems
- Remove `puppet-lint` as it is brought in by `voxpupuli-puppet-lint-plugins`
- Remove `specinfra` as it is brought in by `serverspec`
- Move `serverspec` to system_tests
- Remove `ed25519` and `bcrypt_pbkf` as they are brought in by `net-ssh`
- Remove `rspec-puppet` as it is brought in by `puppetlabs_spec_helper`
- Pin `facterdb` to 1.18 and up as this is the version which adds Ub22.04
- Remove code previously used to retrieve ruby version