Add .stylelintrc.json to @wordpress/create-block

[khoipro]

What problem does this address?

When creating a new block with core blocks, it's requires to modify some BEM Class which generated by core, such as:

.wp-block-group__inner-container

However latest @wordpress/create-block still report violating "Selector should use lowercase and separate words with hyphens selector-class-pattern".

What is your proposed solution?

Add .stylelintrc.json in package @wordpress/create-block to ignore this warning.

{
	"extends": "@wordpress/stylelint-config",
	"rules": {
		"selector-class-pattern": null
	}
}

• Refer with Gutenberg default stylelint config:

  gutenberg/.stylelintrc.json

  Line 11 in d9e7541

  "selector-class-pattern": null,

• Related Issue: stylelint-config: the selector-class-pattern rule rejects some default block, widget, and editor classes #28616

[khoipro]

I think the patch should be there: https://github.com/WordPress/gutenberg/blob/trunk/packages/scripts/config/.stylelintrc.json

I will put my patch tomorrow.

[gziolo]

Should we revisit #28954 instead that tried to make the rule better aligned with what Gutenberg uses? An alternative would be to disable the rule everywhere (in @wordpress/stylelint-config) until we have a better validator.