package is not compatible to eslint v9

[fmacherey]

I updated to eslint v9 and moved to the new flat config.

When using eslint-plugin-json, I am getting the following error:

ESLint configuration in  » plugin:json/recommended is invalid:
	- Unexpected top-level property "files".

Looks like there is something breaking with the new eslint version

[JounQin]

It's documented

https://github.com/azeemba/eslint-plugin-json#basic-configuration-legacy-eslint-format

{
  "extends": ["plugin:json/recommended-legacy"]
}