docs: how to run CLI for development

[abitrolly]

Description

Explain how to run commitlint from the source code.

Motivation and Context

I could not find a way to test new rule from a command line using cloned source code. This should be it. yarn install doesn't make commitlint available.

Is there a better way?

How Has This Been Tested?

Manually yarn run commitlint.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[escapedcat]

Hm, good point.
I usually use this: echo "#123 - test commit" | ./@commitlint/cli/cli.js.
But I guess echo "#123 - test commit" | yarn run commitlint does just the same.

[escapedcat]

Thanks!