Enable unicorn/better-regex (#7991)

* Enable `unicorn/better-regex`

* Spellcheck ignore regex

src/language-css/parser-postcss.js

@@ -464,7 +464,7 @@ function parseNestedCSS(node, options) {
       }
 
       if (name === "at-root") {
-        if (/^\(\s*(without|with)\s*:[\s\S]+\)$/.test(params)) {
+        if (/^\(\s*(without|with)\s*:[\S\s]+\)$/.test(params)) {
           node.params = parseValue(params);
         } else {
           node.selector = parseSelector(params);
@@ -500,7 +500,7 @@ function parseNestedCSS(node, options) {
         ].includes(name)
       ) {
         // Remove unnecessary spaces in SCSS variable arguments
-        params = params.replace(/(\$\S+?)\s+?\.\.\./, "$1...");
+        params = params.replace(/(\$\S+?)\s+?\.{3}/, "$1...");
         // Remove unnecessary spaces before SCSS control, mixin and function directives
         params = params.replace(/^(?!if)(\S+)\s+\(/, "$1(");