High level overview of the changes here:

- The source for the docs content has moved from `docs/content/` to
  `docs/lib/content/`. The generated markdown is still written to
  `docs/content/` but that directory is now ignored from git.
- All generated content sections of the docs have been removed and
  replaced with single placeholder html comments such as `<!--
  AUTOGENERATED CONFIG DESCRIPTIONS -->`
- Placeholders are replaced with generated content only as part of the
  `prepack` step, so generated markdown is no longer checked in to
  source and all docs related `make` commands have been removed
- All docs (and docs related) snapshots have been moved to a single test
  file that outputs command usage and formats it with functions imported
  from `docs/lib/index.js`. So tests will fail if docs content changes
  until `npm run snap` is run.

Closes #5643
Closes #5642
Closes #5630
Closes #5638

BREAKING CHANGE: links generated from git urls will now use `HEAD`
instead of `master` as the default ref

BREAKING CHANGE: the `node-version` and `npm-version` configs have been
removed.

These are only used sparingly by arborist to determine if optional
dependencies should be installed, and during engines checks (which
are only warnings unless `engine-strict` is true.

BREAKING CHANGE: the presence of auth related settings that are not scoped to a specific registry found in a config file is no longer supported and will throw errors

After #5309 moved docs dependencies to proudction deps, we started
failing our daily audit CI check. Currently these deps are production
so they are available when we run `pack`, but they don't need to be
audited since they are never present in our published tarball.

This change runs `audit` on the root CLI and all workspaces within the
`workspaces/` directory, which are the only production workspaces.