Document `--skip-<tool>` options in `lint`/`fix`/`fmt` help-text

[danxmoran]

Is your feature request related to a problem? Please describe.

lint/fix/fmt support the (repeatable) --only flag to specify the tools that should run, but there isn't an easy way to say "run every tool except for XYZ". You can achieve the result you want by passing every tool name except for the one you'd like to exclude via --only, but that's tough to maintain over time as subsystems are added/removed.

Describe the solution you'd like

Support for excluding tools by name. The filter goal/flags support this via a prefix of -, which we could possibly replicate here (i.e. pants lint --only=-pylint). Alternatively we could add a new flag (i.e. pants lint --not=pylint).

Describe alternatives you've considered

We've been working around this by listing out every tool via --only, and have discovered multiple times that we're accidentally skipping a linter in CI because we forgot to update one list or another.

Additional context

lint already has --skip-formatters and --skip-fixers so maybe --skip would make sense for a new option name?

[cognifloyd]

Each backend provides a --<tool>-skip option for this. Black for example has --black-skip
https://www.pantsbuild.org/docs/reference-black

[danxmoran]

🤯 I completely forgot about those options.

I wonder if we should add a note to the help output of lint to remind people about them.