This adds workspaces support to `npm repo` and `npm docs`.

It also updates the usage output to support the -w and -ws parameters
output, and cleans up some unneccessary functions in `run-script` and
`exec`.

PR-URL: #2972
Credit: @wraithgar
Close: #2972
Reviewed-by: @nlf

Implements workspaces for set-script, also refactors tests to mock as
little as possible.

PR-URL: #2998
Credit: @nlf
Close: #2998
Reviewed-by: @wraithgar

PR-URL: #3001
Credit: @wraithgar
Close: #3001
Reviewed-by: @nlf

This got left out of the npm view workspaces PR

It defaults to true, but setting it to any falsey value will tell
`@npmcli/config` not to export it into the environment, and will also
put a remark in the documentation that it is not exported.

PR-URL: #3014
Credit: @isaacs
Close: #3014
Reviewed-by: @nlf

* [#2896](#2896) Provide currentEdge in
  ERESOLVE if known, and address self-linking edge case.
* Add/remove dependencies to/from workspaces when set, not root project
* Only reify the portions of the dependency graph identified by the
  `workspace` configuration value.
* Do not recursively `chown` the project root path.

If a user runs 'npm install -w foo bar baz', that won't set 'bar' and
'baz' as workspace names.  The correct incantation is 'npm install -w
foo -w bar -w baz'.

PR-URL: #3016
Credit: @isaacs
Close: #3016
Reviewed-by: @wraithgar

Adds workspaces configuration to `docs`, `repo`, and `set-script`.

PR-URL: #3013
Credit: @wraithgar
Close: #3013
Reviewed-by: @darcyclarke

While it is somewhat helpful to get reports on this, since it indicates
an underlying problem in Arborist, it's also very disruptive and
unhelpful for users.  As of 2.3.0, Arborist gives us the currentEdge if
available, so we _can_ report on that at least.  If there is no node
_or_ edge, then we just don't say what the current state is, which isn't
useful, but at least is less annoying than a 'property of null'
exception.

PR-URL: #3015
Credit: @isaacs
Close: #3015
Reviewed-by: @wraithgar