Ensure chef related specs are organized in a structure similar to the code

As part of &7730

Chef related specs and files are spread across the spec directory in the following subdirectories

• spec/chef
• spec/gitlab-ctl-commands
• spec/gitlab-ctl-commands-ee
• spec/fixtures
• spec/libraries
• spec/support/shared_examples
• spec/support/shared_objects
• spec/chef_helper.rb

We should consolidate them to a single directory, and mimic the structure of the chef related codebase. So, something like the following

spec
└── chef
    ├── cookbooks
    │   └── <cookbook_name>
    │       ├── libraries
    │       │   └── <library_name>_spec.rb
    │       ├── recipes
    │       │   ├── enable_spec.rb
    │       │   └── <recipe_name>_spec.rb
    │       └── resources
    │           └── <resource_name>_spec.rb
    ├── gitlab-ctl-commands
    │   ├── gitlab_ctl_spec.rb
    │   └── lib
    │       └── util_spec.rb
    └── gitlab-ctl-commands-ee
        └── geo_spec.rb