Don't report errors when validated with @supports

[kkmuffme]

https://developer.mozilla.org/en-US/docs/Web/CSS/@supports

@supports (content-visibility: hidden) {
	.foo {
		content-visibility: hidden;
	}
}

This shouldn't report an error. Same also for e.g. @supports (content-visibility: hidden) and (display: flex) {
Any or conditions or if prefixed with not should continue to report errors just like now.