Disallow invalid uses of default in rule schemas

[not-an-aardvark]

Ajv ignores default in rule schemas if they appear within anyOf or oneOf modifiers. It would be nice to have a rule that warns about these invalid schemas.

module.exports = {
    meta: {
        schema: [
            {
                oneOf: [
                    { enum: ["foo", "bar"] },
                    {
                        type: "object",
                        properties: {
                            foo: {
                                type: "boolean",
                                default: true // invalid
                            }
                        }
                    }
                ]
            }
        ]
    }
    create(context) { /* ... */ }
};

Refs: eslint/eslint#11427

[not-an-aardvark]

Closing in favor of eslint/eslint#11473