fix(biome_css_parser): fixed css @document parser error

[eryue0220]

Summary

Closed: #4258

Test Plan

Add test cases:

@-moz-document url-prefix() {}
@-moz-document url-prefix("https://www.example.com/") {}
@-moz-document url-prefix() {
	body {
		background-color: green;
	}
}
@-moz-document url-prefix("https://www.example.com/") {
	body {
		background-color: green;
	}
}

[codspeed-hq]

CodSpeed Performance Report

Merging #4342 will not alter performance

_{Comparing eryue0220:fix/css-moz-document (b0eb8d5) with main (1b348f4)}

Summary

✅ 101 untouched benchmarks

[chansuke]

https://github.com/biomejs/biome/actions/runs/11424405261/job/31784700204
can you check the code diff below?