Incorrect help information provided on 'dart help doc'

[dgagnon]

1. Using latest dart (3.1.0), issue the following command:

PS E:\Dan\Code\Project Pipeline\flutter-demo-with-docs> dart help doc
Generate API documentation for Dart projects.

For additional documentation generation options, see the 'dartdoc_options.yaml' file documentation at https://dart.dev/go/dartdoc-options-file.

Usage: dart doc [arguments] [<directory>]
-h, --help                  Print this usage information.
-o, --output=<directory>    Configure the output directory.
                            (defaults to "doc\api")
    --validate-links        Display warnings for broken links.  Incompatible with --dry-run.
    --dry-run               Try to generate the docs without saving them.

Run "dart help" to see global options.

2. Then follow the provided link: https://dart.dev/go/dartdoc-options-file ( redirects to https://github.com/dart-lang/dartdoc#dartdoc_optionsyaml )
3. The documentation page contains many incorrect pieces of information. For example:

Auto including dependencies 
If --auto-include-dependencies flag is provided, dartdoc tries to automatically add all the used libraries, even from other packages, to the list of the documented libraries.

Result of this command:

PS E:\Dan\Code\Project Pipeline\flutter-demo-with-docs> dart doc --auto-include-dependencies .
Could not find an option named "auto-include-dependencies".

Usage: dart doc [arguments] [<directory>]
-h, --help                  Print this usage information.
-o, --output=<directory>    Configure the output directory.
                            (defaults to "doc\api")
    --validate-links        Display warnings for broken links.  Incompatible with --dry-run.
    --dry-run               Try to generate the docs without saving them.

Run "dart help" to see global options.

[devoncarew]

We likely need a doc page that's specific to the dartdoc_options.yaml file; that linked page includes additional cli args, including ones we don't expose through dart doc.

cc @srawlins