fix: remove disallowed description property from config

[bmish]

Fixes this comment:

• feat: support ESLint flat config #443 (comment)

Context:

• Custom properties like description not allowed on ESLint flat configs  bmish/eslint-doc-generator#506
• Change Request: Standardize documentation properties (e.g. allow configs to export description) eslint/eslint#17842

This reverts part of:

• docs: auto-generate readme configs list and some rule doc options lists with eslint-doc-generator #416

ESLint no longer allows arbitrary properties like description on configs.

Fixes #478.

[coveralls]

coverage: 100.0%. remained the same
when pulling 1208be0 on bmish:remove-desc-config
into 05bbdcd on platinumazure:main.

[bmish]

@platinumazure can you release a patch release with this?

[bmish]

I'm going to release this since it's a severe breakage.

[platinumazure]

@bmish Thanks for taking care of this and sorry for missing your comments.