fix(schema): add the other format changelogPreset can assume

[vhoyer]

This references the version 2.2.0 from the following repository. https://github.com/conventional-changelog/conventional-changelog-config-spec

Description

Motivation and Context

The current schema only allow for a string based "changelogPreset", but lerna also supports an object syntax for this property.

How Has This Been Tested?

Linked the proposed changes to one of my monorepos' lerna.json by adding a $schema at the beginning of the file, it works.

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)
• Chore (change that has absolutely no effect on users)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[JamesHenry]

Thank you @vhoyer!