Move cookiecutter Tofu to new site environment

[wtripp180901]

• Added new site environment to serve as a base environment for all new cookiecutter environments by default.
• Tofu configuration previously in cookiecutter has been moved to site to receive upgrades from the upstream Tofu.
• Moved ./environments/skeleton to ./cookiecutter.
• Removed environments/common/layouts, the everything templates is now the groups file of the site environment.
• Cookiecutter-defined environments now have site as a "parent" in their ansible.cfg by default. Their Tofu configuration is a module pointing at the site Tofu and they no longer define a groups file (deferred to site).
• .stackhpc environment now based on the site environment.

Note: topology aware scheduling is also now off by default, guidance on re-enabling has been added to the production docs

Warning

Will cause merge conflicts with existing site environments. To resolve:

• For divergent default values for variables in environments/site/tofu/variables.tf, changes should generally be rejected
• All other Tofu changes in environments/site/tofu should generally be accepted (unless site specific resources have previously been defined)
• The contents of environments/site/inventory/group_vars/all should be your existing yaml files
• Changes to the :children of existing groups in environments/site/inventory/groups should generally be rejected. New groups which have been added should generally be accepted, unless the feature the group enables is not desired

[sjpb]

Few comments, looks structurally sound though!

[sjpb]

Typo, query, no need to rerun CI.

[wtripp180901]

looks like it has here https://github.com/stackhpc/ansible-slurm-appliance/blob/feat/site-tofu/cookiecutter/%7B%7Bcookiecutter.environment%7D%7D/ansible.cfg, probably some github diff weirdness

[sjpb]

From merge test:

• topology: lets remove from site/groups, and add a note in production to say consider turning this on if cluster is VMs AND its either in one AZ or AZ is configured by rack, and point to docs.

Other than that looks fine

[sjpb]

LGTM