First try scss when there's an @import with comma (#2225)

It's annoying that the less parser is so lenient that it drops things instead of throwing :(

Fixes #2125

src/parser-postcss.js

@@ -209,7 +209,7 @@ function requireParser(isSCSS) {
 }
 
 function parse(text) {
-  const isLikelySCSS = !!text.match(/(\w\s*: [^}:]+|#){|\@import url/);
+  const isLikelySCSS = !!text.match(/(\w\s*: [^}:]+|#){|\@import[^\n]+(url|,)/);
   try {
     return parseWithParser(requireParser(isLikelySCSS), text);
   } catch (e) {