Update default pattern library settings in getting-started.md

[bmihelac]

Description

Pattern library settings notes wrong default settings:

    "SECTIONS": (
        ("components", ["patterns/components"]),
        ("pages", ["patterns/pages"]),
    ),

    "SECTIONS": (
        ("atoms", ["patterns/atoms"]),
        ("molecules", ["patterns/molecules"]),
        ("organisms", ["patterns/organisms"]),
        ("templates", ["patterns/templates"]),
        ("pages", ["patterns/pages"]),
    ),

Updating this also requires using molecules instead of components in other places of the document.

Checklist

• [ ] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ x] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] New and existing unit tests pass locally with my changes
• [ ] I have added an appropriate CHANGELOG entry